Finders unveils Lerokis ore reserve upgrade in Wetar copper project

By Romel S. Gurky

ASX-listed Finders Resources Limited reported on Tuesday significant increases in the Mineral Resource and the Ore Reserve at the Lerokis deposit, which is the second mine planned within the company?s Wetar Copper Project, in Indonesia?s Maluku Province.

The company said in a statement that the updated Lerokis Mineral Resource estimate is the first revision since the Hellman and Schofield estimate was undertaken in 2009. That estimate formed the basis for the Feasibility Study released in November 2011.

The database used in the current estimate incorporates assay data from 73 additional drillholes, of which 60 were drilled during the 2017 campaign. The remaining 10 historic geotechnical and metallurgical holes and 3 exploration holes were resampled and included in the updated estimate.

This additional data has resulted in interpreted geometallurgical domains for the first time while the remaining estimation parameters and methodology are largely unchanged from that used previously and reported in the Mineral Resource and Ore Reserve update released to the ASX on 16 December 2016.

Tables 1 and 2 summarize the Mineral Resource estimate by JORC category and by geometallurgical domain

Table 1 - Lerokis Mineral Resource Estimate (>0.5% Cu)

Classification	Tons (Mt)	Cu (%)	Cu (Metal Tons)
Measured	2.80	2.88	80,700
Indicated	0.10	0.89	900
Inferred?	0.02	0.95	200
Total?	2.92	2.80	81,800

Table 2 - Lerokis Mineral Resource Estimate by
Geometallurgical Domain (>0.5% Cu)

Domain	Classification	Tons (Mt)	Cu (%)	Cu (Metal Tons)
PBX (Pyrite Breccia)	Measured?	1.19	3.29	39,200
	Indicated	-	-	-
	Inferred	-	-	-
	Sub-Total	1.19?	3.29	39,200
MPY (Massive Pyrite)	Measured?	1.09?	1.54	16,800
	Indicated	0.04	0.91	400
	Inferred	0.02?	0.95	200
	Sub-Total	1.15?	1.51	17,300
BKO (Black Ore)	Measured?	0.44	5.47	24,000
	Indicated	-	-	-
	Inferred	-	-	-
	Sub-Total	0.44	5.47	24,000
SBX (Silica Breccia)	Measured?	0.08?	0.81	600
	Indicated	0.06	0.87	500
	Inferred	-	-	-
	Sub-Total	0.14?	0.84	1,200
Total		2.92	2.80	81,800

Finders said the updated Mineral Resource estimate has increased the contained copper metal by 34 percent or 20,800 tons from the previous estimate of 2.6 million tons at 2.3 percent copper for 61,000 tons of copper metal.

The updated Lerokis Ore Reserve estimate is derived from the Mineral Resource block model. Block and grade data were constrained by interpreted geometallurgical domains and only Measured and Indicated category blocks were considered in the development of the Ore Reserve estimate. Tonnages were reported on a dry basis.

Gemcom Whittle pit optimisation software was used to determine the optimal pit shell and an actual mine design was developed to honour that shape. Whittle is an industry standard tool which combines the geological, geotechnical, spatial, grade, metallurgical, cost and revenue characteristics of the deposit to determine the optimal mining limits and sequence for a given set of assumptions.

The updated Ore Reserve estimate has increased the contained copper metal by 29 percent or 17,200 tons from the previous estimate of 2.5 million tons at 2.3 percent copper for 59,000 tons of copper metal. The additional copper metal is notionally equivalent to approximately 5 months of additional copper production based on the 2013 Bankable Feasibility Study (BFS) financial model recovery estimate of 66 percent.

Table 3 summarizes the Ore Reserve estimate by JORC category.

Table 3 ? Lerokis Ore Reserve Estimate (Cu >0.5%)

Classification?	Tons (Mt)	Cu (%)	Cu (Metal Tons)
Proved??	2.67	2.84	75,800
Probable??	0.04	0.84	300
Total	2.71?	2.81	76,200
Waste	2.62	?	?
Strip Ratio	0.92	?	?

Managing Director Barry Cahill commented: ?This Mineral Resource and Ore Reserve update for the company?s second open pit mine at Lerokis confirms our long held belief that there was good opportunity to significantly increase the contained copper metal. The magnitude of these increases and the favourable results from the metallurgical testwork program are pleasing and demonstrates potential for further upside to the Wetar Copper.?

Editing by Reiner Simanjuntak