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Altona Mining: JORC 2012 Ressourcenschätzung für Little Eva Vorkommen

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    27. Mai 2014                                                                                                                             ASX: AOH, FSE: A2O

JORC 2012 RESSOURCENSCHÄTZUNG FÜR LITTLE EVA VORKOMMEN

Altona Mining Limited ('Altona? oder das 'Unternehmen?) gibt mit Freude eine JORC 2012 konforme Mineralische Ressourcenschätzung für ihr zu 100% im Eigentum befindlichen Little Eva Kupfer-Gold Vorkommen im nordwestlichen Queensland bekannt. Die Schätzung basiert auf neuen geologischen Modellen die sich aus einem sehr ausgedehnten Arbeitsprogramm ableiten das aus erneuten Bohrlochmessungen und Datenvalidierung bestand. Es wurden keine neuen Bohrungen durchgeführt und es gibt keine materiellen Änderungen zur früheren Schätzung vom 19. Dezember 2011.

Aktualisierte Little Eva Ressource bei 0,2% Kupfergrad als Betriebsschwellengrenze wie folgend:

Tonnen

(Mio.)

Kupfer

(%)

Gold

(g/t)

Enthaltenes Kupfer

(Tonnen)

Enthaltenes Gold

(Unzen)

Gemessene

37.1

0.60

0.09

222,000

112,000

Angezeigte

45.0

0.46

0.08

205,000

108,000

Geschlussfolgert

23.9

0.50

0.10

119,000

75,000

Total

105.9

0.52

0.09

546,000

295,000

Eine ausführliche Tabelle mit verschiedenen Betriebsschwellengrenzen finden Sie im Appendix 1 und eine Beschreibung der Beurteilungskriterien und Berichtskriterien die in der Schätzung benutzt wurden und diese detailliert aus Tabelle 1 zeigen gemäß dem Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (The JORC Code, 2012) finden Sie in Appendix 2.

Das Little Eva Projekt in Deutscher Synchronisation: http://bit.ly/1mgw7cF

Die frühere Schätzung vom Dezember 2011 lag bei 100,3 Mio. Tonnen mit 0,53% Kupfer und 0,09g/t Gold was 534.000 Tonnen Kupfer und 284.000 Unzen Gold ergab.  

Im Vergleich zur ersten Schätzung stieg die Tonnage um 6% an, das enthaltene Kupfermetall um 2% und das Goldmetall um 4%. Das Vertrauen in die Schätzung stieg nun auf 78% in die Gemessenen und Angezeigten Kategorien von zuvor 69% in der Schätzung von 2011. Beide Schätzungen berücksichtigen nicht die oxydische Mineralisierung.

Ein extensives Bohrlochbewertungsprogramm das 84% aller Ressourcenbohrungen abdeckte und ein Datenvalidierungsprogamm konzentrierten sich auf:

? Weitere Validierung und Korrekturen der Bohrkragenansätze, lochabwärts gerichtete Untersuchungen und Probendaten.

? Vereinheitlichung der Beschreibungen und Codierung der Lithologie, Verwitterung, Mineralisierung und Alterung.

? Bestimmen der Mineralisierungskontrollen.

? Aufbau eines 3D geologischen Modells aus den interpretierten Abschnitten.

? Aufbau eines Ressourcenmodells basierend auf den neuen geologischen Interpretationen unter Einsatz der gleichen Schätzmethode (MIK) wie bei der Schätzung 2011.

Das Little Eva vorkommen ist ein Proterozoische Eisen-Oxid-Kupfer-Gold Vorkommen das in der Region üblich ist. (z.B. Ernest Henry Mine).  Beherbergt wird es in einem steil abfallenden linsenartigen metamorphosen vulkanischem Komplex (Little Eva Igneous Complex) der ca. 1,2 Km lang ist und bis zu 500 m breit. Der Komplex wird von variablen amygdaloidalen und flusspatig-phyrischen dazwischen liegenden vulkanischenm Felsen mit leichten felsichen Intrusiven beherbergt.

Hauptlithologien sind verschieden verwittert in Ansammlungen die aus Albit, Clacit, Quarz, Magnetit, Hämatit, Epidot, Chlorit, Cchalcopyrit, Pyrit und Chalcocit bestehen. Die häufigste intensive mineralisierung zeigt variable Venen und Breccias und intensiv verwitterte Zonen die mit Mächtigkeiten von 1-40 m variieren und steil nach Osten abfallen im Norden des Vorkommens und nach Nordwesten in den zentralen und südlichen Teilen des Vorkommens. Die Grade variieren auf bis zu 5% Kupfer und 1,6 g/t Gold in diesen Zonen was Durchschnitten von 0,84% und 0,13g/t jeweils entspricht. Die Mehrheit des vulkanischen Komplexes ist verwittert und mineralisiert mit tiefgradigem Kupfer welches weit verteilt ist.

Der vulkansiche Komplex ist in spätere Strukturen gebunden und wird von einer Reihe Unterstrukturen durchzogen.

Der vulkanische Komplex liegt innerhalb eines feinkörnigen und regelmäßigen kalkhltigen Metasediments. Metasedimente direkt neben dem vulknaischen Komplex können verwittert in gleichen Ansammlungen auftreten zum vulkanischen Komplex hin.

Die Hauptmineralisierung hat einen Deckel von ca. 15 bis 30 m Stärke der aus Kupferoxidmineraliserung besteht. (Goethit, Malachit).

Geologie und Mineralisierungen sehen Sie in den Abbildungen 1-5.

Für Fragen wenden Sie sich bitte an:

Alistair Cowden           

Managing Director               

Altona Mining Limited           

Tel: +61 8 9485 2929            

altona@altonamining.com      

James Harris          

Professional Public Relations

Perth

Tel: +61 8 9388 0944        

james.harris@ppr.com.au

Jochen Staiger

Swiss Resource Capital AG

Tel: +41 71 354 8501

info@resource-capital.ch

Es gilt ausschließlich das Englische Original dieser Pressemitteilung

Über Altona Mining Ltd.

Altona Mining Limited ist ein Kupferproduzent in Finnland und besitzt ein großes Kupferentwicklungsprojekt in Australien.

Das Outokumpu Projekt des Unternehmens im Südosten Finnlands nahm die Produktion Anfang 2012 auf. Das Projekt schließt die Kylylahti-Untertagemine mit einer Jahreskapazität von 600.000 t und die Luikonlahti-Mühle ein. Die durchschnittliche Jahresproduktion liegt bei 9.000t Kupfer, 9.000 Unzen Gold und 1.600t Zink mit der Möglichkeit einer Produktionserweiterung. Die regionalen Ressourcen sind in zwei stillgelegten Minen und 4 noch nicht abgebauten Ressourcen innerhalb von 30km der Luikonlahti-Mühle beherbergt. Finnland ist Mitglied der Eurozone und hat eine lange Bergbauhistorie, eine stabile Steuergesetzgebung (20%) und keine weiteren Abgaben.

Altonas weiteres Herzstück ist das Roseby-Kupferprojekt nahe Mt. Isa in Queensland und eines der größten noch nicht entwickelten Kupferprojekte Australiens. Das erste angestrebte Entwicklungsziel mit 7 Mio. t pro Jahr ist die Kupfer-Gold-Tagebaumine und Aufbereitungsanlage Little Eva. Little Evas angestrebte Jahresproduktion1 soll bei 38.800 t Kupfer und 17.000 Unzen Gold für mindestens 11 Jahre Produktionsdauer liegen. Es konnte eine endgültige Machbarkeitsstudie abgeschlossen werden und das Projekt ist voll genehmigt. Altona ist derzeit in Verhandlungen mit potenziellen Partnern, um die Finanzierung dieses Großprojektes ermöglichen zu können.

Altona Mining ist an der Australian Securities Exchange und der Börse Frankfurt notiert.

1Siehe ASX-Pressemitteilung 'Cost review Delivers Major Upgrade to Little Eva' vom 13. März 2014, die die Informationen hinsichtlich dieses Produktionsziels und die auf diesem Produktionsziel basierenden Finanzprognosen skizziert. Diese Pressemitteilung ist bei www.altonamining.com oder www.asx.com.au zu finden. Das Unternehmen bestätigt, dass alle wesentlichen Annahmen, die das Produktionsziel unterstützen und die auf diesem Produktionsziel basierenden Finanzprognosen, die in der oben genannten Pressemitteilung erwähnt werden, weiterhin gültig sind und sich nicht wesentlich geändert haben. Es gilt ausschließlich das Englische Original dieser Pressemitteilung.

Aussage der kompetenten Person

Die Informationen in dieser ASX-Pressemitteilung, die sich auf Explorationsergebnisse, Mineralressourcen oder Erzvorräte beziehen, basieren auf Informationen, die von Dr. Alistair Cowden BSc (Hons), PhD, MAusIMM, MAIG, Managing Director von Altona zusammengestellt wurden. Er ist Mitarbeiter des Unternehmens und verfügt über ausreichendes Wissen und Erfahrung über diesen hier vorliegenden Vererzungs- und Lagerstättentyp. Seine Tätigkeiten qualifizieren ihn als kompetente Person gemäß den Regeln des 2012 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Dr. Alister Cowden stimmt den hier eingefügten Informationen, die auf seinen Informationen basieren, in Form und Kontext je nach Auftreten zu.

Weiter geht es im Englischen Original:

JORC 2012 and Competent Persons Statement

The Company has reported Resources and Reserves according to the 2012 edition of the JORC Code and a full 'Table 1? is appended.

1. Mineral Resources estimation: The Little Eva Mineral Resource Estimate that is reported in this ASX Release is based on information compiled by Mr Jani Impola, MSc, MAusIMM who is a full time employee of Altona Mining Limited and Mr Ian Glacken, MSc, FAusIMM(CP), CEng, who is a full time employee of Mineral Resource advisory firm Optiro, and who both have sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which they are undertaking to qualify as a Competent Person as defined in the 2012 Edition of the ?Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves? (The JORC Code).  Mr Impola and Mr Glacken consent to the inclusion in the release of the statement of their undertaking the resource estimation process in the form and context in which it appears.

2. Responsibility for entire release: Information in this ASX Release that relates to Exploration Results, Mineral Resources or Ore Reserves and commentary in Table 1 on mining, metallurgy and environment is based on information compiled by Dr Alistair Cowden BSc (Hons), PhD, MAusIMM, MAIG and Dr Iain Scott PhD Min. Processing, BSc Met. (Hons), MAusIMM who are both a full time employee of the Company and who have sufficient experience which is relevant to the style of mineralisation and type of deposit under consideration and to the activity which they are undertaking to qualify as a Competent Person as defined in the 2012 Edition of the ?Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves?. Dr Alistair Cowden and Dr Iain Scott consent to the inclusion in the report of the matters based on their information in the form and context in which it appears.

Figure 1:  Plan of interpreted Geology and block model of copper grade distribution for the Little Eva deposit

W:\_Transfer\Marianne\Section A 4p4.tif

Figure 2: Cross Section A showing geology, drilling and block model of copper distribution (refer Figure 1)

W:\_Transfer\Marianne\Section B BM 4p4_Crop.tif

Figure 3: Cross Section B showing geology, drilling and block model of copper distribution (refer Figure 1)

W:\_Transfer\Marianne\Section B Geology 4p4_Crop.tif

Figure 4:  Cross Section B showing geology and drilling (refer Figures 1 and 3)

W:\_Transfer\Marianne\Section C 4p4_Crop.tif

Figure 5:  Cross Section C showing geology, drilling and block model of copper distribution (refer Figure 1)

W:\_Transfer\Marianne\Legend.jpg

Appendix 1

Table 1:  May 2014 Little Eva Mineral Resource Estimate at 0.20% copper cut-off grade

Tonnes

(million)

Copper

(%)

Gold

(g/t)

Contained Copper

(tonnes)

Contained Gold

(ounces)

Measured

37.1

0.60

0.09

222,000

112,000

Indicated

45.0

0.46

0.08

205,000

108,000

Inferred

23.9

0.50

0.10

119,000

75,000

Total

105.9

0.52

0.09

546,000

295,000

Table 2:  May 2014 Little Eva Mineral Resource Estimate at 0.30% copper cut-off grade

Tonnes

(million)

Copper

(%)

Gold

(g/t)

Contained Copper

(tonnes)

Contained Gold

(ounces)

Measured

24.6

0.78

0.12

192,000

94,000

Indicated

26.8

0.60

0.10

160,000

84,000

Inferred

14.6

0.66

0.13

96,000

60,000

Total

66.1

0.68

0.11

448,000

238,000

Table 3:  December 2011 Little Eva Mineral Resource Estimate at 0.20% copper cut-off grade (provided for comparative purposes only)

Tonnes

(million)

Copper

(%)

Gold

(g/t)

Contained

Copper

(tonnes)

Contained

Gold

(ounces)

Measured

36.3

0.63

0.08

227,000

99,000

Indicated

32.7

0.48

0.08

156,000

81,000

Inferred

31.5

0.48

0.10

150,000

104,000

Total

100.3

0.53

0.09

534,000

284,000

Table 4:  December 2011 Little Eva Mineral Resource Estimate at 0.30% copper cut-off grade (provided for comparative purposes only)

Tonnes

(million)

Copper

(%)

Gold

(g/t)

Contained

Copper (tonnes)

Contained

Gold

(ounces)

Measured

24.6

0.81

0.10

198,000

76,000

Indicated

20.5

0.62

0.09

127,000

62,000

Inferred

18.5

0.64

0.13

119,000

79,000

Total

63.6

0.70

0.11

444,000

217,000

Note: Totals may not match sub-totals due to rounding.

Table 5:  Summary of Mineral Resource Estimates for the Cloncurry Copper Project

DEPOSIT

TOTAL

CONTAINED

METAL

MEASURED

INDICATED

INFERRED

Tonnes

Grade

Copper

Gold

Tonnes

Grade

Tonne

Grade

Tonnes

Grade

million

Cu

%

Au

g/t

tonnes

ounces

million

Cu

%

Au

g/t

million

Cu

%

Au

g/t

million

Cu

%

Au

g/t

COPPER GOLD DEPOSITS

Little Eva

105.9

0.52

0.09

546,000

295,000

37.1

0.60

0.09

45.0

0.46

0.08

23.9

0.50

0.10

Ivy Ann

7.5

0.57

0.07

43,000

17,000

-

-

-

5.4

0.60

0.08

2.1

0.49

0.06

Lady Clayre

14.0

0.56

0.20

78,000

85,000

-

-

-

3.6

0.60

0.24

10.4

0.54

0.18

Bedford

1.7

0.99

0.20

17,000

11,000

-

-

-

1.3

1.04

0.21

0.4

0.83

0.16

    Sub-total

129.1

0.53

0.10

684,000

409,000

37.1

0.60

0.09

55.3

0.49

0.09

36.7

0.51

0.12

COPPER ONLY DEPOSITS

Blackard

76.4

0.62

-

475,000

-

27.0

0.68

-

6.6

0.60

-

42.7

0.59

-

Scanlan

22.2

0.65

-

143,000

-

-

-

-

18.4

0.65

-

3.8

0.60

-

Longamundi

10.4

0.66

-

69,000

-

-

-

-

-

-

-

10.4

0.66

-

Legend

17.4

0.54

-

94,000

-

-

-

-

-

-

-

17.4

0.54

-

Great Southern

6.0

0.61

-

37,000

-

-

-

-

-

-

-

6.0

0.61

-

Caroline

3.6

0.53

-

19,000

-

-

-

-

-

-

-

3.6

0.53

-

Charlie Brown

0.7

0.40

-

3,000

-

-

-

-

-

-

-

0.7

0.40

-

    Sub-total

136.7

0.61

-

840,000

-

27.0

0.68

-

25.0

0.64

-

84.7

0.59

-

TOTAL

265.8

0.57

0.05

1,524,000

409,000

64.1

0.63

0.05

80.3

0.54

0.06

121.4

0.56

0.04

See ASX release of 23 October 2007 and 26 July 2011 (Longamundi, Great Southern, Caroline and Charlie Brown), 23 April 2012 (Bedford, Ivy Ann and Lady Clayre), 03 July 2012 (Blackard and Scanlan) and 22 August 2012 (Legend) for full details of resource estimation methodology and attributions.

Note:  All figures may not sum exactly due to rounding.

Little Eva is reported above a 0.2% copper lower cut-off grade, all other deposits are above 0.3% lower copper cut-off grade.

JORC Table 1

The table below is a description of the assessment and reporting criteria used in the Little Eva Resource and Reserve Estimation that reflects those presented in Table 1 of The Australasian Code for the Reporting of Exploration Results, Mineral Resources and Ore Reserves (The JORC Code, 2012).

Criteria

Commentary

Sampling Techniques and Data 

Sampling techniques

? The dataset incorporates 316 Reverse Circulation (RC) and 34 RC holes with diamond tails holes for a total of 57,559 metres of drilling.

? 3,845 of a total 53,911 (7.1%) samples were drill core and 50,066 (92.9%) samples were RC chips.

? No other sample types were used in the resource estimate.

? Holes were nominaly drilled at dip angles of either 60o or 90o.  Wherever possible, holes were planned to intersect mineralisation at optimal true width angles.

? 94% of RC drilling was sampled at one metre intervals with the remainder sampled at either 2, 3, 4 or partial metre lengths. Approximately 2kg of each interval was submitted for geochemical analysis.

? Each sample was crushed and pulverised to produce a representative charge for assay.

? 67% of diamond core was sampled at 1 metre intervals with a further 22% sample at 2 metre intervals and the remainder sampled at variable lengths according to geology.

? Drill core sampling was guided by geology. Either half or quarter core was submitted for analysis to the laboratory.

Drilling techniques

? RC drilling included 5.25?, 5.375?, 5.5? and 6? size face-sampling hammers.

? HQ, HQ3, NQ, NQ2, NQ3 and BQ core sizes were used in diamond drillholes.

? Most recent diamond drill core has been marked using inner tube inlaid systems such as ?Ezy-Mark? while the method for orientation of core sourced from older generation holes is uncertain.

Drill sample recovery

? Diamond Core recovery is good, averaging 94%.

? RC samples were visually checked for moisture and contamination and recoveries estimated from the sample volume.

? Best practice methods were used for diamond coring to ensure the return of high quality core samples.

? During RC drilling, the cyclone and splitter were routinely cleaned, ensuring no material build up.

? Due to the subjective nature of RC sample recovery estimation, no reliable relationship with grade variation has been established.  No relationship between drill core recovery and grade has been established.

Logging

? A re-logging campaign was completed during 2013. A total of 48,725 metres (64% of drilling were re-logged for lithology, alteration, mineralisation characteristics, weathering/oxidation and structure.  Logging information was recorded on paper and was later transferred into the database. 

? Diamond core was geologically logged using predefined logging codes for lithological, mineralogical and physical characteristics (such as colour, weathering and lithology). In addition, structural measurements of major features were collected.

? RC logging was completed in single or multi-metre intervals.

? Earlier drilling was logged onto paper and transferred to a digital form for loading into the drill hole database. More recently logging was completed directly onto a laptop in the field using a proprietary geological logging package with in-built validation. Logging information was reviewed by the responsible geologist prior to the final database upload.

? Chip trays were collected for each of the RC intervals and core trays were photographed.

? Geotechnical logging of diamond core consisted of recording core recovery, RQD, fracture frequency and nature, core state (i.e. whole, broken) and hardness.

? Logging was generally qualitative in nature with the exception of structural and geotechnical measurements and the estimation of sulphide percentages.

? Drill core was photographed and digitally stored for visual reference.

? Lithological logs exist for 100% of the Little Eva database. Approximately 64% of all metres were relogged during 2013; this equates to approximately 84% of holes used in the resource estimation.

Sub-sampling techniques and sample preparation

? CRA Exploration (CRAE) diamond drill core collected during the period 1963-1996 was sampled as sawn half core on approximately 2 metre  intervals.

? Sampling of diamond core generated by later exploration companies was guided by logged visual mineralisation. Samples were mostly 1 metre intervals, except where sampling was more selective to preserve geological boundaries. Core was generally halved for initial assay sampling. If later umpire or additional metallurgical sampling was required, the remaining half core was split to yield quarter core samples.

? For Altona RC drilling, a trailer mounted cyclone and triple deck splitter were used to collect representative chip samples from the drill rig in 1 or 2 metre intervals. Wet intervals were sub-sampled with a scoop or spear.

? There is little information available on the RC sampling procedures used by CRAE in the period 1963-1996.  11% of the RC drillholes used in the estimate are CRAE RC holes from the period 1988-1996. 

? Drillholes with identified quality issues have been excluded from the estimation data set.

? The preparation techniques employed for the diamond and RC samples followed industry best practice and were completed by the relevant laboratory.

? While peparation techniques vary they usually comprise  oven drying, crushing and pulverising samples to established parameters.

? There is little information available on the RC Quality Assurance and Quality Control (QAQC) sampling procedures employed by CRAE in the period 1963-1996. 

? From 2002 to 2006 the following QAQC practices applied:

? Regular field duplicate sampling of RC samples at a ratio of 1:37; in 2004 duplicates were sent to both the primary and secondary laboratory.

? Post campaign duplicate re-sampling of 5% to 10% of bulk rejects (2004 only).

? Insertion of standard samples at a 1:40 ratio (2004 only).

? Insertion of blank samples at a 1:40 ratio (2004).

? Screen fire assay checks against fire assay for gold on a campaign basis.

? From 2006 more rigorous QAQC practices applied:

? RC field duplicates were collected either directly from the cyclone or as a second sample from the riffle splitter. Drill core duplicates were either collected by halving the sampled half core or were split from pulped half core.

? Primary field duplicates were collected at a 1:20 ratio, with a second duplicate collected at a 1:40 ratio. These second duplicates were then submitted to a check laboratory for umpire testing.

? Universal field QAQC procedures included the insertion of certified reference standards at a 1:20 ratio to samples. Standards included multiple elemental abundances reflecting the variations of those elements in the Little Eva mineralisation.

? Certified or in-house quartz sand blanks were inserted at regular intervals of 1:40 samples.

? Duplicate scatter plots for data generated later than 2003 indicate fair to excellent precision for copper and gold results.

? Control plots for Standards submitted after 2003 show few outliers, indicating good to excellent accuarcy.

? The mass of RC chip samples received by laboratories averaged 2.136 kg. This is an appropriate sample size for this style of mineralisation and elemental abundance.

Quality of assay data and laboratory tests

Copper assaying was completed at a variety of different laboratories utilising various preparation and direct analytical methodologies.

? Laboratories

? Australian Laboratory Services (ALS)

? Australian Mineral Development Laboratories (AMDEL)

? AMMTEC Laboratory

? Classic Laboratory Services

? SGS / Analytical Laboratories (ANALAB)

? Ultra Trace Pty Ltd

? Preparation Methods

? Aqua Regia (~36% of total)

? Perchloric Acid

? Mixed Acid (Hydrochloric, Perchloric, Hydrofluoric) (~57% of total)

? 4 Acid (Near Total) (~4% of total)

? Total Digest

? Analytical Methods             

? Atomic Adsorption Spectroscopy (AAS) (~57% of total)

? Inductively coupled plasma mass spectroscopy (ICPMS)

? Inductively coupled plasma optical emission spectrometry (ICPOES) (~4% of total)

? Inductively coupled plasma atomic emission spectroscopy (ICPAES) (~33.7% of total).

Gold assaying was completed at two laboratories with the following preparation and analytical methods.

? Laboratories

? Australian Laboratory Services (ALS)

? SGS / Analytical Laboratories (ANALAB)

? Preparation Method

? 3 Acid

? Fire Assay

? Analytical Method

? Atomic Adsorption Spectroscopy (AAS)

? No geophysical tools were used for collection of elemental assay data relevant to the Little Eva 2014 resource.

? Laboratory QAQC involves the use of external company and internal lab standards using certified reference material, blanks, splits and replicates as part of the in-house procedures. Specific QAQC protocols vary across organisations.

? Umpire laboratory check samples were submitted from 2004 to indepentently verify reported results.

? The umpire sample checks indicate a high degree of precision for primary copper assay results generated after 2004, with little evidence for bias.

? Umpire checks upon gold assays indicate some discordance in 2004 drilling results (a minor proportion of the database) and good reliability since that year.

Verification of sampling and assaying

? Several assay validation checks have been completed at different stages of the exploration  process. Numerous external parties have reviewed significant intersections during the life of the project.

? There are 10 sets of twinned drillholes at Little Eva dataset. Overall mineralisation trends are replicated in twin holes, though variation exists in tenor and location of mineralisation. This may sometimes be attributed to downhole survey issues or in other instances drill directions relative to mineralisation dip or discontinuity in small scale mineralisation pods. In isolated cases diamond drilling suggests thin, high grade material may be reflected as broader, moderate zones of mineralisation. The discontinuity is largely reflected in the nugget effect highlighted by variography.

? Historic paper delivered assay results have been retained in hard copy format and/or converted to scanned digital versions. More recent assay results were delivered in electronic format.

? Data is entered into the database using standardised protocols which preserve the upload user ID and time/date stamping.

? Subpopulations of historic database records have been verified against original paper records

? Delivered digital results and the entire database are stored upon company servers which are protected by multiple tiers of backup protocols. Additional data storage and protection is provided by the current laboratory provider ALS - which retains a digital copy of data generated.

? No assay results have been adjusted prior to upload to the database.

Location of data points

? Three dimensional spatial locations were calculated using collar locations and downhole survey measurements with curved path geometries.

? In 2002, all historic drill collars except four were surveyed by contractor Hugh Patterson with a Differential Global Positioning System (DGPS). During the period 2003-2011, licensed surveyors M H Lodewyk carried out DGPS collar surveys at the conclusion of annual programs. Altona purchased a DPGS unit in 2011 and has surveyed all holes since this time.

? All drillhole collar spatial locations are recorded within the resource database using the Map Grid of Australia (MGA) Zone 54 datum.

? A summary of downhole survey methods at Little Eva is given below.

? Most collars have been surveyed by both magnetic and gyroscopic means.

? 12% of holes have a compass survey at the drillhole collar only. This was common practice for historic holes, drilled prior to the year 2000.

? 11% of holes have a gyro survey at the drillhole collar only;

? 56% of holes have magnetic downhole camera surveys, usually at 50 metre intervals.

? 3% of holes have magnetic downhole multi-shot surveys, usually at 10 metre intervals.

? 18% of holes have downhole gyroscopic surveys, usually at 3 or 5 metre intervals.

? Variable quantities of magnetite present in the rocks at Little Eva affects magnetic survey and compass readings, particularly within the intermediate host rock. 

? The resource estimate was completed using the MGA54 Zone 54 national grid as datum.

? The majority of drilling was completed within the ?Local Eva New? local grid which has its northing axis oriented parallel to the strike of the ore body. Drillhole collar locations were transformed from the local grid to the MGA54 Zone 54  national grid within the database using the two common point method.

? The surface topography was constructed from survey data in the form of 0.5 metre contours, collected by licensed surveyors Bennett & Bennett Surveyors and Planners. The DGPS collar survey location for Little Eva drillholes was compared to this topographic surface, and the average variation was 16cm. This confirms that the topographic surface is high quality.

Data spacing and distribution

? Drilling has dominantly been completed on 50 metre spaced lines oriented east-west in local grid orientation.

? 50% of the drilling is aligned at 55-60 degrees to east.

? 33% of the drilling is subvertical or vertical.

? 13% of the drilling is aligned at 55-60 degrees to west.

? 4% of the drilling is aligned in other directions.

? 27 sections between local grid coordinates 25400mN-26450mN have been drilled to a 50m x 40m drilling density. This represents 1,300 metres of strike length across 95% of the resource, which is deemed appropriate for establishing geological continuity and to understand grade continuity.  Local scale variability has been addressed by selecting a suitable estimation method - Multiple Indicator Kriging.

? CRAE composited 5,586 single metre RC chip samples into two metre intervals for holes LE034-LE076, representing 9.6% of all sampling metres.

? Universal Resources composited all samples in its 2002 RC programme as two metre intervals. Specific intervals of interest were then resplit as 1 metre samples following the result of intial assays.

? RC holes drilled after 2002 were sampled as single metre intervals and no compositing applied.

Orientation of data in relation to geological structure

? Nominal east-west drill sections are normal to the strike of the mineralisation.

? The dip of the mineralisation varies from 50 degrees to the east to subvertical.  Local grade continuity follows the dip of the mineralisation in the north; flatter local grade continuity is noted in the central and southern domains. The bulk of the drilling intersects local grade continuity at between 60 and 90 degree angles.

? A small number of drillholes were drilled parallel to mineralisation trends, mostly in the strongly mineralised northern portions of Little Eva. These drillholes were excluded from the estimation process. As such, no biases are expected from the drilling direction.

Sample security

? Industry standard sample security measures were employed. Samples were transported to the Company depot at the end of each working day and secured. Sample dispatch through reputable commercial freight companies was completed as soon as was practically possible.

Audit or reviews

? A comprehensive audit of the sampling and assaying procedures used by the company and of the results of the quality control sampling programme was carried out by independent consultants McDonald Speijers in 2006, with no significant adverse findings.

? Sampling and QC procedures employed by CRAE prior to 1996 have been poorly documented. Reports state that procedures conformed to the CRAE standards of the time.

Estimation and Reporting of Mineral Resources

Database integrity

? Data used for estimation is stored within a SQL Server database and is managed using DataShed software. The structure of the drilling and sampling data is based on the Maxwell Data Model.

? Prior to 2006 data was logged onto field sheets which were then entered into the data system by data capture technicians.

? Since 2006 data has been logged directly into digital logging systems and uploaded to the database by the database administrator.

? Laboratory data has been received in digital format and uploaded directly to the database since 2002.

? In both cases the data was validated on entry to the database, or on upload from the earlier MS Access databases, by a variety of means, including the enforcement of coding standards, constraints and triggers. These are features built into the data model that ensure that the data meets essential standards of validity and consistency.

? Original data sheets and files have been retained and are used to validate the contents of the database against the original logging.

? Certain drillholes, such as those associated with unreliable or non-representative data including auger holes, open percussion holes, trenches or poorly located holes, were excluded for resource calculation purposes.

? Extensive validation of existing collar, downhole survey and assay data was completed in 2013/2014. Validation steps included:

? All collar surveys were compared against original records.

? Downhole surveys were compared against original records.

? A representative population (11.5%) of copper and gold assays in the database were validated against original records. Selected assays represent all main drilling programmes by different owners between 1978 and 2011. Errors were identified in less than 0.001% of the database, confirming that the copper and gold assays in the database are of high quality.

? Drillhole collar locations were compared to the topographic surface.

? Downhole deviations of all drillhole traces were examined and problematic surveys were excluded.

? The downhole survey datum was checked to ensure grid transformations were correctly applied.

? All data (e.g. assay, bulk density, RQDs, core recovery) was checked for incorrect values by deriving minimum and maximum values.

? Lithology data was checked to ensure standard rock type codes were used.

? Meta-data fields were checked to ensure they were populated and that the data recorded was consistent.

Site visits

? Multiple site visit have been completed by the Competent Persons other than Mr Ian Glacken.

Geological interpretation

? Confidence in the geological interpretation of the deposit is moderate to high. The spatial extent and geometry of separate lithological components is well constrained by geological knowledge acquired through the relogging of historic drill core and chips completed in 2013.

? The deposit is characterised by an Iron-Oxide-Copper-Gold style of mineralisation common in the local region and is hosted within a metamorphosed igneous complex dominated by variably amygdaloidal and feldspar-porphyritic intermediate igneous rock crosscut by later felsic intrusives. The igneous complex is situated within Proterozoic age fine grained, frequently calcareous metasediments

? Primary lithologies have been altered to varying degrees of intensity to assemblage comprising of haematite, albite, carbonate, silica, magnetite, epidote, chlorite, chalcopyrite, pyrite and chalcocite..

? The lithologies are  inferred to have been cross cut by several generations of faults.

? The geological context has been defined by diamond and RC drilling. This information is supported by surface mapping and geophysical interpretation, including magnetics and gravity.

? A new geological interpretation was completed for 13 detailed 100 metre spaced sections. Prior interpretations were used for other sections.

? Geological surfaces were interpolated to creation of three dimensional solids for mineralisation and lithology.

? All holes, including those between detailed sections, were then used to snap lithological and mineralisation contacts in three dimensional space

? There are no alternative detailed interpretations of geology. The geology interpretation has been refined and is believed to be highly robust.

? The current geology model was updated in 2013 after an extensive re-logging campaign.

? Economic mineralisation is mostly hosted within a fault-bounded package of dominantly intermediate igneous rocks. This package is mostly well-mineralised; however, a weakly mineralised to barren ?halo? exists at its eastern and southern margin with metasediments. The western mineralisation boundary is generally parallel to the contact between the igneous package with metasediments. Thus in less densely drilled areas (mostly at depth), the wireframe of the igneous package was used to constrain mineralisation.

? A felsic intrusive body is present along the faulted western contact between the igneous package and meta-sediments. Mineralisation within this felsic intrusive varies to that in the nearby intermediate igneous rock. Strongly mineralised zones recognised in adjacent intermediate rocks can be traced into the felsic intrusive. The mineralisation that surrounds these strongly mineralised zones is not as well developed within the felsic intrusive; thus this was separated into a unique weakly mineralised domain for grade estimation.

? The main mineralisation domains, North, Central, South and Southeastern were defined using grade constraints in conjunction with lithological contacts between the igneous complex and metasedimentary rocks.

? A general grade cut-off of 0.15% copper was used to define the boundaries between mineralised and weakly-mineralised or unmineralised domains.

? The North domain is defined by generally higher copper grade averaging approximately 1% and hosted by steaply east dipping sheet of intensly altered igneous complex. Southern and western contacts are interpreted to be fault structures.

? The Central domain is defined by moderate (0.3% to 0.5% copper) grade mineralisation hosted by the altered igneous complex and bounded by fault structures to the north, south, and west. Subdomains of breccia hosted high grade mineralisation (modelled using 0.5% copper cut off) strike northeast and dip steeply to the northwest.

? The South domain is generally low (<0.3% copper) to moderate (0.3% to 0.5% copper)  grade mineralisation hosted by the altered igneous complex and bounded by fault contacts. Dip of mineralisation is shallower than the in the central domain.

? The Southeastern domain forms a block of igneous complex seperated from the main mineralisation by fault structures. Internaly this block is structurally divided into several low, moderate or high grade sheets of mineralisation with varying strikes and dips, though generally to the southwest.   

All domains were subdivided using a base of oxidation surface to separate oxide mineralisation and primary sulphide mineralisation.

Dimensions

? The main zone of mineralisation inclusive of the North, Central and South domains, strikes north-south to NNW-SSE and the dip varies between 60 degrees to East in the north to subvertical in the central and south domains.

? Mineralisation has a strike length of 1300 metres and the width varies from 20 metres (north) to over 300 metres (central).  Mineralisation has been intersected between the elevations of 165mRL and -200mRL.

? The deposit remains open to the south and at depth.

Estimation and modelling techniques

? Multiple Indicator Kriging (MIK) was used to estimate copper grades into parent blocks (25m x 25m x 10m)  using up to eleven indicator cut-offs with associated indicator variograms per domain for primary mineralisation.  Ordinary block kriging was used to interpoloate indicators.  Indicators were post-processed to calculate e-type mean grades (for validation) and the grades and fractions above cut-offs for a selective mining method. An Indirect lognormal support correction was applied for the change of support from points to Selective Mining Unit (SMU) support (6.25m x 6.25m x 5m). The distribution above the topmost threshold was modelled using a hyberbolic extrapolation which was fitted to the actual composite data from the bin threshold up to a top cut value.  The MIK copper grades at the panel support were post-processed to yield SMU-support grades using a local MIK (LMIK) algorithm based upon the local Uniform Conditioning (LUC) algorithm.  Gold grades were estimated at SMU support using the copper and gold grades and a collocated cokriging method, which preserves the generally-high copper-gold correlation.  Both copper and gold were reported above a 0.2% copper cut-off at the SMU support.

? Ordinary Kriging (OK) estimates for copper were also made at the SMU scale to provide a ranking model for the LMIK post-processing

? 14 unique domains have been estimated. Two estimation passes were used for all the domains.  The first pass has search radii of 150m x 150m x 30m with a minimum of 12 and a maximum of 24 samples in search. The second pass searched 250m x 250m x 50m with a minimum of 6 and maximum of 24 samples.  Search ellipse orientations were the same as variography orientations. No octant restrictions were used, and as such the maximum distance of extrapolation from data points is equal to the search radii specified above. Most of the blocks were informed in the 1st pass and commonly the 24 sample restriction was met before reaching maximum search distances.

? Sample data was composited to a one metre length. A minor quantity of small composite lengths remained and these were excluded from grade estimation.

? Composites were declustered using a 50 x 50 x 40 cell declustering method.

? Extreme outliers of the gold sample population were top cut. No top cut was applied to copper.

? Directional variograms were modelled for whole domains and indicator variograms for selected indicator percentiles (up to 11). Modelled indicator variograms showed 50-70 metre variogram ranges with 20-45% nuggets variances.

? Geovariance?s Isatis and Snowden?s Supervisor software was used for variography.

? The public domain Stanford University GSLIB software  was used for resource estimation. Dassault Systemes? Surpac software  provides a front-end interface for GSLIB, and this was used to run GSLIB?s DOS executables.

? Isatis was used for the LMIK copper post-processing and the collocated kriging for gold estimation.

? An OK estimation was compiled and comparison with the E-type (panel average) estimate was within acceptable limits.

? Comparison with the previous May 2011 Little Eva MIK model showed no material change.

? No by-product metallurgical assumptions have been built into the estimate.  These are not relevant to the extraction of copper and gold by conventional means.

? No internal, external dilution or ore loss due to deleterious elements or other non-grade variables of economic significance were modelled.

? The block model was constructed using 25m x 25m x 10m  parent block size with standard subcelling to 6.25m x 6.25m x 5m , which represents the mining SMU.  Kriging Neighbourhood Analysis was performed to optimise the block size, search distances and sample numbers.

? The selective mining unit (SMU) size was defined at 6.25m x 6.25m x 5m . This is in line with assumptions made regarding current mine plans, production rates and equipment sizes.

? Only copper and gold were integrated in the resource calculation. Correlation between these two variables is moderate to good, with domain sample correlation coefficients varying between 0.6 and 0.7. The collocated cokriging of gold makes use of the copper-gold correlation to pair high copper and gold grades.

? Top cut analysis was carried out for all the domains for copper and gold. The top cut was decided using the following criteria:

? Continuity of the high grade tail in the grade histogram

? Log probability plots

? Change in the coefficient of variation (CV)

? Spatial location and clustering of high grade samples

? Mean and variance plot analysis for sensitivity of mean grade to top cutting

? Top cuts were applied to gold as top cut analysis indicated that extreme outliers had some influence on the sample population.

? No top cut was applied to the copper as top cut analysis indicated minimal influence from extreme outliers on the sample population. However, copper top cuts were selected and used for the maximum data value allowed for upper tail extrapolation, a parameter used during MIK post-processing to calculate the recoverable resource.

? An external and independent review of this Mineral Resource estimate was undertaken by Optiro Consultants.  Internal validation was carried out by Altona, comparing the MIK E-type and the OK panel estimates and this was reviewed by Optiro and found to be satisfactory.  SMU-level gold estimates were validated against gold composites and the copper-gold correlation at the SMU scale was compared to the composite correlation.  Visual validation of all models was carried out in plan and section.

Moisture

? Tonnes have been estimaed on a dry basis.

Cut-off parameters

? Resources are reported above 0.20% and 0.30% copper cut-offs using a recoverable resource technique with the change of support to the SMU scale.  By definition this reflects the planned scale of mining and production.

? These cut-off grades have been adopted as they permit a bulk tonnage operation.

Mining factors or assumptions

? The resources are estimated and reported using a recoverable resource technique (LMIK) which assumes selective mining at the scale of the SMU.

? The SMU selected was 6.25m x 6.25m x 5m.

? The selected SMU is compatible with a large scale bulk tonnage mining operation.

Metallurgical factors or assumtpions

? Extensive mineralogical and metallurgical testwork has been completed on the Little Eva resource.

? Testwork indicates that a 96% copper recovery will be achieved at a concentrate grade of 25% copper. Gold recovery is 85% at a concentrate grade of 4 g/t.

? No metallurgical assumptions have been built into the resource estimate and none are necessary.

Environmental factors or assumptions

? The Little Eva resource is a component of the Little Eva Development Project and accordingly is encapsulated within the granted Environmental Management Plan (EMP).

? The EMP considers a broad range of environmental considerations including:

? Flora and Fauna

? Soils

? Radiation

? Atmospheric Emissions

? Hydrogeology

? Baseline and ongoing studies form part of EMP requirements.

? Analysis of simulated tailings fluids and solids prepared through laboratory scale test work indicates favourable environmental results. Simulated sulphide and oxide tailings were found to be benign in terms of potential for formation of acidic, saline or metalliferous drainage.

? Consequently, no adverse environmental considerations have been built into the resource model.

Bulk density

? In total 1,862 bulk density measurements have been taken from Little Eva core.

? Samples were sourced from multiple holes across the extent of the deposit in both the oxide and sulphide mineralisation zones. Spatially, samples cover 1,000m of strike length and 200m of depth extent.

? Measurements were completed using the industry standard weight in air / weight in water method.

? The mean bulk density value for each modelled lithology was used for tonnage calculations.

? The lithology wireframes and oxidation surfaces were used to flag the block model and the bulk density samples.

? For each lithology within fresh rock, the mean bulk density value was calculated from sample data and assigned to the block model. A value of 2.8 t/m3 was assigned to intermediate rock; 2.63 t/m3 for felsic intrusive; and 2.7 t/m3 for meta-sediments.

? Insufficient bulk density measurements existed within the oxide zone, and a nominal value of 2.5 t/m3 was assigned to the block model. The oxide zone is not included in the Mineral Resource.

? Bulk density has no correlation with copper or gold grades.

? Bulk density has a broad correlation with lithology and alteration.

? Bulk density averages for fresh rock were calculated from statistically signficant volumes of samples. A total of 1386 samples were used for intermediate rock; 371 for meta-sediments; and 70 for felsic intrusive. The felsic intrusive comprises a relatively small volume of the Mineral Resource.

Classification

? Classification for Little Eva is based upon the continuity of geology, mineralisation and grade, using drillhole and density data spacing and quality, variography and estimation statistics (number of samples used, estimation pass, and slope of regression).

? Mineral resources have been classified on the basis of confidence in geological and grade continuity using the drilling density, geological model, modelled grade continuity and conditional bias measures (slope of the regression and Kriging efficiency) as criteria.

? Measured Mineral Resources have been defined in areas of 50m x 40m  drill spacing with low variance in grade and good grade and geological continuity.

? Indicated Mineral Resources have been defined in areas of 50m x 40m drill spacing where grade variance is moderate.

? Inferred Mineral Resources have defined generally in areas of 100m x 100m drill spacing.  Inferred Mineral Resources have been modelled down to 100m RL (250 metres below surface).

? The classification appropriately reflects the quality of and confidence in the grade estimates expressed by the Competent Persons.

Audits or reviews

? An external and independent review of the resource estimate was undertaken by Optiro consultants.

Discussion or relative accuracy/confidence

? No formal confidence intervals have been derived by geostatistical or other means; however, the use of quantitative measures of estimation quality such as the Kriging efficiency and the slope of regression allow the Competent Person to be assured that appropriate levels of precision have been attained within the relevant resource confidence categories.

? These levels of confidence and accuracy relate to the quarterly estimates of grade and tonnes for the deposit, which have been used in the Definitive Feasibility Study updated and released on 13 March 2014.


Für den Inhalt der Pressemitteilung ist der Einsteller, Altona Mining Ltd., verantwortlich.

Pressemitteilungstext: 19407 Wörter, 319523 Zeichen. Als Spam melden


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