White Cliff Minerals Ltd Stock Market Press Releases and Company Profile
Metallurgical Test-Work Results - Aucu Gold Deposit
Metallurgical Test-Work Results - Aucu Gold Deposit

Perth, May 23, 2017 AEST (ABN Newswire) - White Cliff Minerals Limited (googlechartASX:WCN) ("White Cliff" or the "Company") is pleased to report that metallurgical test work on samples taken from the 2016 drilling program at the Aucu Gold Deposit in Kyrgyz Republic have delivered excellent gold recoveries. The metallurgical test work was carried out by the Bureau Veritas Minerals Laboratory in Perth.

Highlights

- Metallurgical test-work reveals excellent gold recoveries at the Aucu Gold Deposit
- Mining Optimisation Study Update

Summary - Gold Metallurgy

Metallurgical tests were performed on 14 drilling composites representing 96 one metre drill samples. The samples came mainly from the newly discovered Quartz Zone which has an average gold grade of 9.5 g/t gold and an average copper grade of 0.64% copper.

One composite contained over 1% copper but very little gold. The other 13 composites had significant gold and copper values, averaging 10.6 g/t gold and 0.85% copper. Comparison of fire assay gold analyses with Leachwell bottle roll analyses indicated greater than 96% free milling gold for 10 of the composites. Two composites had about 76% and one composite had 36% free milling gold; these three composites averaged about 2.6% copper which may have affected the Leachwell assays. Screen fire assays showed that on average one third of the gold occurred as relatively large metallic grains.

Summary - Copper Metallurgy

Sequential leach tests quantified the various types of copper mineralisation (oxides, secondary copper sulphides and primary copper sulphides) in each sample. Results showed that:

- approximately 34% of the copper is present as copper oxide (azurite and malachite);
- 20% of the copper is present as secondary copper sulphides (chalcocite and neotoesite); and
- 44% of the copper is present as primary copper sulphides (chalcopyrite).

This is consistent with observed geology. The composition of copper types in each hole varies widely and is related to the amount of weathering the ore interval has been exposed too. Samples closer to the surface or a major fault zone tend to be much more oxidised.

Aucu Gold Deposit- Metallurgy Summary

The Company will undertake further metallurgical testing of copper and gold recovery via a combination of gravity concentration and froth floatation. This would produce saleable high-grade gold/copper concentrates. At this stage of the project, this appears to be the most attractive processing method. It avoids cyanide leaching and associated environmental management problems. Summary metallurgical tables are provided on page three of the release (see the link below).

Gravity recoverable gold averages 88.6% based on the 69 composites (182 samples) tested in 2016 (see ASX release dated 18 February 2016). Gravity concentration testing has not been conducted for the 2017 composites at this stage. However, the high levels of free milling gold and coarse particulate gold seen in the current results are positive indicators.

Approximately 64%of the copper occurred as primary and secondary sulphides which are readily recovered to high-grade concentrates by froth floatation. The remaining 34% of the copper occurs as oxides minerals; these are generally more difficult to recover to concentrates. Achievable recovery levels and concentrate grades will be investigated in the planned test work.

Commentary

Managing Director Todd Hibberd commented that, "The Aucu gold and copper deposit is shaping up as a major find. It displays all the characteristic of a world class deposit including excellent metallurgy, very high gold recoveries, an exceptionally high gravity gold component, a high average gold grade, visible gold in outcrop at surface and multiple mineralised shear zones that extend kilometres".

"These factors, combined with strong government support for new mines, a new five year exploration licence in a location with access to infrastructure such as water, power, roads and a skilled mining workforce, make this a remarkable project".

"The 2017 exploration program has commenced and once the required tracks have been prepared drilling will begin, initially on a 300 metre strike extension of the Quartz Zone. Drilling has also been planned across the project focussing on increasing the current inferred resource along strike".

Mining Optimisation Study Update

The Company is currently finalising the mining optimisation study. The study will evaluate how much of the existing resource can potentially be mined based on standard mining parameters. The study will produce a series of optimal mining shells based on these standard mining parameters. The pit shells provide a guideline on the possible size and depth of open pit designs based on the current inferred resource. The mining study allows the Company to examine various mining scenarios and provides information on where to most economically target infill drilling to enable conversion of the existing inferred resource into an indicated resource. The study will be reported once finalised.

Summary metallurgical tables are provided on page three of the release (see the link below).

The metallurgical results tabulated above in Table 1 and 2 (see the link below) consist of most of the mineralised intervals intersected in the 2016 drilling programs. Samples were collected from each metre drilled via a 3 tier riffle splitter which collects 12.5% of each metre. These 3kg RC samples were collected and sent to the Kyrgyz laboratory where they were crushed to 2mm and sub-sampled to collect two 100 gram samples.

The remaining samples were transported to the Bureau Veritas Minerals Pty Limited Laboratory in Perth, Western Australia where they were riffle split and combined into bigger samples (composites) consisting of each mineralised interval. The composite was riffle split into two samples and one sample was retained. The other sample was pulverised to 90 percent passing a 75 micron (0.075mm) screen. A small 100 gram sample was extracted and analysed for gold to provide a head grade for the metallurgical trial. The balance of the sample was used to conduct the metallurgical test work.

Gravity recoverable gold is the gold that can be extracted by cyanide leaching from the gravity concentrated ore after it has been milled to around 75 microns.

Overall recoverable gold is the gold that can be extracted from both the concentrate ore and from the residual ore using conventional cyanide leaching processes.

To view tables and figures, please visit:
http://abnnewswire.net/lnk/01DY16KN

Contact

Todd Hibberd
Managing Director
T: +61-8-9321-2233
W: www.wcminerals.com.au



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