KAZ Minerals has been wholly acquired by Nova Resources BV to support the Company’s pursuit of a capital-intensive strategy focused on long-term growth.
KAZ Minerals Limited is a high growth copper company focused on large scale, low cost, open pit mining in Kazakhstan. It operates the Aktogay and Bozshakol open pit copper mines in the Abay and Pavlodar regions of Kazakhstan, three underground mines and associated concentrators in the Abay and East regions of Kazakhstan and the Bozymchak copper-gold mine in Kyrgyzstan.
Vostoktsvetmet and KAZ Minerals Bozymchak LLC are wholly-owned subsidiaries of KAZ Minerals.
Summary:
Most of the deposits of the East Region are of the volcanogenic massive sulphide (VMS): Orlovsky, Artemyevsky, Irtyshsky underground mines.
Orlovsky is an active underground mine exploiting a large, polymetallic, high grade, and gold rich VMS deposit. It comprises the Main Orebody, which comprises an upper and lower part with an irregular pod-like shape, 20° to 30° dip to the SW, average thickness of 35m and down-dip extent of 600 m. It is now almost worked out, with the remaining resources consisting of remnant blocks distributed in the lower part of the orebody and representing some 25% of the whole deposit. A 0.85 Mt oxidised cap on the upper part of the orebody has been excluded from the resources since until now, no technology has been successfully developed to treat it.
350 m to the SW of the lower part of the Main Orebody is the New Orebody comprising a southern portion with a 10° to 15° dip to the SW and thickness of up to 56m and a northern portion with very high grade and thickness of 5-20 m. The combined New Orebody occupies a surface area in long section of some 250 m by 150 m and accounts for the rest of the resources in the deposit.
Artemyevsky is an operating underground mine exploiting a larg, high grade, polymetallic, gold and silver-rich VMS deposit. A number of different steeply dipping ore bodies have been identified in the deposit, the most important of which is the Main Orebody, with a strike length of 1,300 m and maximum thickness of 200 m. This is the sole source of ore at the present time, with working on the 7, 8, 9 and 10 Levels. The higher-grade but less continuous Talovskaya Orebody is located 50-150 m in the footwall of the main Orebody, while the Kamishinskaya orebody forms a protective pillar below an old open pit and to protect the underground workings from flooding.
There are further six orebodies that form series sub-parallel lenses gently pitching to the east of the Main and Talovskaya orebodies.
The ore showsa vertical gradation through the individual bodies of polymetallic ores at the top, barite/polymetallic ores, polymetallic ores, copper/zinc ores and copper ores at the base. There are copper rich mineralised zones below these orebodies within the footwall volcanics of the Tavolka formation.
Irtyshsky is an operating underground mine exploiting a polymetallic volcanogenic massive sulphide (VMS) deposit of average size and grade. The mineralisation is of lenses with extensive strike extents but more limited down-dip persistence. There are three principal ore bodies: Main, South East, No 2.
Irtyshsky Principal Orebodies:
Main:
- Orebody Strike length - 2,500 m;
- Down-dip length - 750 m;
- Thickness - 3.5 m.
South East:
- Orebody Strike length - 3,000 m;
- Down-dip length - 400 m;
- Thickness - 2.7 m.
No 2:
- Orebody Strike length - 1,600 m;
- Down-dip length - 300 m;
- Thickness - 1.35 m.
The orebodies pitch slightly to the NW with their long axes roughly parallel. The average strike of the Irtyshsky ore body is NW-SE and the dip of the ore body is steep to sub- vertical (70-80°). The ore body is gently folded with secondary thickening of the ore lenses in the fold axes. The copper and zinc grades increase with increasing depth from surface. Most mining is currently taking place in the lower parts of the Main (12 and 13 levels) and SE (11 level) orebodies. The No 2 Orebody is not being mined at the present time.
The Bozymchak deposits were generated by intrusion of a large granitoid stock with pinkish-grey porphyritic granites of the Dzhalgyzuriuk massif into carbonate cauntry rocks of Devonian and Carboniferous age.
Mineralization is generally in skarn zones, in the form of disseminated sulphides with associated gold. The major sulphide component is chalcopyrite with lesser bornite and covellite; there is some rare presence of sphalerite and arsenopyrite. Surface oxide mineralization is only weakly developed and is primarily marked by the occurrence of malachite. The skarn mineralization is of garnet-wollastonite and garnet-pyroxene types; metamorphosis of limestone and dolomite has occurred locally to form marble and siliceous limestone. The thickness of the skarn horizon varies from a minimum of around 7 m up to 85 m.
To the east of the main central deposit sulphide zones are found which contain chalcopyrite, pyrite and pyrrhotite, with, in this zone, serpentinites which are the products of alteration of pyroxenite; some fibrous asbestos is also found.
The Bozymchak deposit comprises four sectors separated as discrete areas by faulting:
- South-western sector;
- Central sector;
- Eastern sector;
- Davan sector.