Inter-Citic Minerals Inc.

Inter-Citic Minerals Inc.

March 02, 2009 09:00 ET

Inter-Citic Reports on First Stage Metallurgical Results From Its Dachang Gold Project

Global composite recovers 94% of the gold into a final cleaner concentrate mass of 6.2% w/w, assaying 57.7 g/t gold. Overall gold recovery to concentrate of 96% with high concentrate grade of approximately 30 g/t gold.

TORONTO, ONTARIO--(Marketwire - March 2, 2009) - Inter-Citic Minerals Inc. (TSX:ICI) ("Inter-Citic" or "the Company") President and CEO James Moore, is pleased to report the metallurgical results from test work conducted on a bulk composite sample from the Dachang Gold Project is now nearing completion.

Results to date demonstrate that high recoveries of gold (96%) can be achieved using conventional flotation methods. The concentrate produced contains 30 g/t gold and is considered to be marketable. Further test work has shown that the rougher concentrate can be upgraded to 57.7 g/t gold through regrind and cleaning stages. This results in an overall recovery of 94% of the gold into a final cleaner concentrate with a mass of only 6.2% w/w.

James Moore, President and CEO of Inter-Citic, said: "We are obviously very pleased with these results since they confirm that we are able to produce a marketable high-grade, low mass concentrate from the ore at Dachang. Confident that we have optimized gold recovery to the sulphide concentrate, we are now continuing with test work to identify an optimal final process route that includes treatment of the bulk sulphide concentrate using a broad range of available processes."

The test work was conducted at the AMMTEC laboratories in Perth and was supervised by Metallurg Pty Ltd. The test work program included crushing, grinding, and flotation to produce a bulk sulphide concentrate. Further treatment of the flotation concentrate product is being undertaken by testing refractory process routes such as ultra-fine grind ("UFG") / CIL, two-stage roast/UFG/CIL, the Activox Process® (oxidation/UFG/CIL) and BIOX®/CIL.


The testwork program was based on the following procedures:

- Metallurgical testwork was conducted on a global bulk composite, derived from drill core representing the various lithology zones from the Dachang deposit.

- Replication of a three-stage crush and single stage mill with a rougher/cleaner flotation circuit to produce a saleable bulk sulphide concentrate.

- Testing of various refractory sulphide process routes to produce bullion on site.


Metallurgical testwork was carried out on a global composite prepared from a representative blend of the various lithology types and grade ranges present at Dachang. A separate split of the global composite sample was sent for the comminution testwork.

Sample quantity requirements were estimated and drill-hole intercepts selected for the following:

- Comminution testwork to characterise the grindability of the various ore types to define parameters to allow design and simulation of the proposed grinding circuit.

- Metallurgical testwork to establish the optimum process route and treatment conditions based on composite and variable samples representing the major ore types, gold grades and geographical locations.


On the basis of macroscopic and microscopic studies, paragenesis, type of occurrence and metallogenic character, the mineralization at Dachang is divided into two types:

(a) gold-sulphide-alteration cataclastic rock type; and,

(b) gold-pyrite vein type.

The host rocks at Dachang are sedimentary, composed of mainly argillite and sandstone and are locally silicified and carbonatized with local evidence of chloritization and sericitization. Disseminated pyrite, arsenopyrite and stibnite are present.

Physical Characteristics:

- The Bond Ball Mill Work Index for the global composite sample was 13.8kWh/t (at a grind size P80 of 75 microns) and is considered medium to hard.

- Liner and media consumption are expected to be moderate.

Metallurgical Characteristics:

- Rougher flotation conducted on the global composite recovered approximately 96% of the gold into a rougher concentrate mass of 12.4% w/w, assaying 29.5 g/t gold.

- Further upgrading of the rougher concentrate with a regrind and cleaning stages recovered approximately 94% of the gold into a final cleaner concentrate mass of 6.2% w/w, assaying 57.7 g/t gold.

- Ultra-fine grinding (P80 of 5 microns) of the rougher concentrate product, in conjunction with CIL, resulted in a low gold leach recovery of 27%, after 48 hours. Reagent consumptions for lime and cyanide were high.

- Two-stage roast/UFG/CIL testing on the rougher concentrate product resulted in an improved metallurgical performance, with 78% of the gold recovered after 48 hours of intensive cyanidation leaching. Lime and cyanide consumptions were very high at 4.47 kg/t and 81.1 kg/t.

- Testing of the Activox Process® (atmospheric oxidation/UFG/CIL) achieved very high sulphur oxidation of 99.8%. Gold and silver recoveries were 83.91% and 86.50% respectively, after 48 hours. A maximum gold leach recovery of 89% was achieved after 8 hours of leaching, before preg-robbing took place. Further optimization of CIL test parameters is required, including testing of increased carbon levels in the CIL and the addition of kerosene to overcome the preg- robbing.

- The ore can be classified as refractory with gold locked in arsenopyrite.

- Bio-leach amenability testing is underway to determine whether the Dachang sulphide concentrate is amenable to processing using the BIOX® process.

Results of the Rougher / Cleaner Flotation Test are summarized below in Table 1:

Grind Test Float Conc. Concentrate Assay Metal Distribution
Size No. Conc. Mass Au Ag S As Au Ag S As
(microns) (Wt%) (g/t) (g/t) (%) (%) (%) (%) (%) (%)
75 WH 1567 Rougher 12.4 29.5 3.9 9.7 4.6 95.67 91.72 97.86 95.70
45 Cleaner 6.2 57.7 6.8 19.1 9.0 93.56 79.98 96.65 93.24

The proposed process route for Dachang consists of a primary grind (P80 of 75 microns) followed by a conventional rougher/scavenger circuit, with regrinding of the bulk sulphide concentrate to a P80 grind size of 45 microns. The reground bulk sulphide rougher concentrate then requires three stages of cleaning to produce a high grade saleable concentrate. Depending on market TC/RC it could be possible to sell the lower grade rougher concentrate product in China. Further market research needs to be carried out.

This test work was conducted at the AMMTEC laboratories in Perth. AMMTEC Pty Ltd. is one of the largest metallurgical and mineral testing consultancies in the world. Metallurgical test work was completed under the supervision of Mr Gary Patrick, an external consultant to the Company. Mr Patrick has sufficient experience, which is relevant to the style of mineralization and type of deposit under consideration and to the activity which he is undertaking to qualify as a Competent Person as defined in the 2004 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Patrick consents to the inclusion in this report of the matters based on his information in the form and context in which it appears.

Mr. Michael W. Leahey, P.Geo., the Company's internal Qualified Person under the requirements of National Instrument 43-101, has reviewed a copy of this press release.

On Behalf of the Board:

James J. Moore, President & CEO


Toronto-based Inter-Citic Minerals Inc. is an exploration and development company with properties in the People's Republic of China, including its Dachang Gold Project in Qinghai Province. Inter-Citic is listed on the TSX under the symbol ICI. Inter-Citic's website is

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