Two main types of mineralisation are recognised at Blanket mine, namely disseminated sulphide replacement reefs (“DSR”) and quartz-filled reefs and shears.

DISSEMINATED SULPHIDE REPLACEMENT REEFS
DSRs host the best grades and comprise the bulk of the ore shoots. These zones have a silicified core with finely-disseminated arsenopyrite. Relatively high grades are found in a package of silicified biotite chlorite schist with irregular quartz stringers and disseminated and stringer arsenopyrite in the fabric planes. Due to lesser silicification, abundant biotite characterise the margins of these mineralised zones and as a result they have a lower gold content. Disseminated sulphide-replacement Mineral Deposits range up to 50 m in width with a strike of between 60 m and 90 m. Free-milling gold constitutes up to 50% of the total metal content with the remainder locked in the arsenopyrite. The ore is not refractory despite its association with arsenopyrite. Generally, plant recoveries in excess of 90% are achieved.

- QUARTZ-FILLED REEFS AND SHEARS
The second type of mineralisation is the quartz-filled reefs and shears. Two quartz shears are mined at the Blanket Mine: the Blanket Quartz Reef and the Eroica Reef. These reefs have long strikes, however, they are not uniformly mineralised. Continuous pay shoots of over 100 m on strike are not present. The Quartz Reef at the Blanket Mine has a surface strike of approximately 500 m, but economic mineralisation is restricted to three 90 m long shoots which were defined on surface by the early workers (AGS 2006). Quartzfilled reefs display a much wider grade range compared to the DSR deposits. On average, these shears are of a higher grade and are used in blending the ore to the mill. Dominant ore minerals are native gold and galena although arsenopyrite becomes more prevalent below the 470 m elevation.

Wall rock alteration typically comprises silica-pyrite-muscovite within a broader carbonate alteration halo. Quartz-carbonate altered rock forms the most commonly recognised alteration assemblage.

The deposits may have a vertical extent of up to 2 km, demonstrate extensive down-plunge continuity, and lack pronounced zoning. The ore mineralogy is dominated by gold, pyrite and arsenopyrite. Subordinate minerals such as galena, chalcopyrite, pyrrhotite, sphalerite, tellurides, scheelite, bismuth and stibnite also occur. Sulphide mineralogy commonly reflects the litho-geochemistry of the host rock with arsenopyrite being the most common sulphide mineral in metasedimentary host rocks and pyrite or pyrrhotite being more typical in metamorphosed igneous hosts. The gangue and alteration mineralogy is dominated by quartz and carbonate (ferroan dolomite, ankerite, siderite, calcite) with subordinate albite, fuchsite, sericite, muscovite, chlorite and tourmaline

Blanket Mine uses mining methods that are commonly employed and well-understood by Greenstone Belt miners who generally have to deal with steep tabular to massive Mineral Deposits. Since the nature of the Mineral Deposits varies, the exact mining practices are tailored to suit the specific attributes of each particular Mineral Deposit. The mining methods employed represent experience gained from many years of mining. Two types of mining methods are used at the Blanket Mine:
- Underhand stoping in the narrow Mineral Deposits.
- Long hole stoping in the wider Mineral Deposits.

The Mineral Deposits can be accessed on several main levels: 7 Level, 9 Level, 14 Level, 18 Level and 22 Level. In-between these levels cross-cuts are cut every 30 m from where diamond drilling is used to locate ore shoots for development planning. Most of the development is within mineralised zones, except when developing transfer levels between Mineral Deposits. Such development is treated as waste.

Stoping preparations in narrow Mineral Deposits (<3.0 m) begin by mining box raises sited at 10 m intervals from the footwall of the Mineral Deposit. In wider Mineral Deposits (>3.0 m), air loader operated draw points are mined instead of boxes to facilitate long hole open stoping which generates large rocks. Underhand bench stoping is usually applied in the narrow Mineral Deposits and allows for control of the stoping width (+/-2 m) and dilution.

As at June 2011, underground drilling equipment comprised seventy Seco 23, Seco 25, Seco 215 jackhammers and Seco 36 (Konkola) drifters. The jackhammers are mainly used for development and the drifters for production (long hole drilling). Tramming of ore and waste is done by LM56/57 air loaders, grandby cars, cocopans and battery-operated locomotives.

The Blanket gold Plant consists of a conventional crushing, milling and CIL, batch elution and smelting configuration with a current capacity of 40 ktpm. The crushing and milling circuits are designed to process RoM. However, the CIL and downstream circuits were designed to treat tailings dam material at a rate of about 110 ktpm (or 3,800 tonnes per day). More recently, historic tailings and RoM were treated in the CIL plant at a combined rate of approximately 100 ktpm to 120 ktpm. The tailings treatment was stopped about three years ago. The CIL is currently used exclusively for treatment of RoM at a rate of 30 ktpm to 35 ktpm. The retention time in the CIL circuit is as high as 72 hr as a result of the lower tonnage throughput.

The plant consists of the following circuits:-
- jaw crushing;
- cone crushing in closed circuit with a screen;
- primary rod mill in open circuit;
- ball mill in closed circuit with cyclones;
- gravity circuit;
- dewatering cyclones;
- CIL;
- combined elution and electrowinning;
- smelt house;
- carbon re-activation in a kiln;
- reagent make-up and dosing circuits; and
- water recycling and storage.

The ore is fed over 14" x 24" jaw crushers to reduce the top size from -300 mm to less than 80 mm. Tramp iron magnets (located ahead of the crushers) remove scrap iron before it enters the cone crushers. This is important as any iron products from underground will cause major damage to the crushers if allowed to enter the crusher bowl. The crushed ore is stored on a 900 tonne open stockpile from where material is fed to the cone crushers.

The rod mill feed bin live capacity is small which, in turn, requires that the crushers operate on a threeshift cycle to ensure that the rod mills have adequate feed for continuous operation. There are plans to install additional storage capacity which will result in reduced operating costs in the crushing circuit. The cone crushers can then operate for fewer hours at a higher throughput thereby reducing operating unit costs and introducing more flexibility.

There are three 6.5 ft. x 12 ft. rod mills which operate in parallel. Each feed belt has a mill feed mass meter?which is used to control and measure the mill feed rate. The foundations of the previous mills were in the?process of being demolished which leaves adequate space for future expansion.

Approximately 45% to 50% of the gold production is recovered as gravity gold. Concentrate from the Knelson Concentrators is stored and re-concentrated on a Gemini table every 24 hours with the tailings recycled back into the circuit. Gemini table concentrates go for direct smelting whilst the tailings are pumped to the classifying hydro cyclone. The Knelson Concentrator tails are pumped through cyclones, the underflow of which reports to the open-circuit regrind ball mill.

The product from the Knelson tails cyclone overflow and the regrind mill discharge is pumped into the CIL plant. The CIL consists of one pre-aeration tank and eight leach tanks where alkaline-cyanide leaching and simultaneous absorption of dissolved gold onto granular activated carbon takes place.

Oxygen generated from a pressure oxygen plant is added into the first CIL tank; liquid oxygen is also available in the event of the oxygen plant being out of circuit for maintenance or breakdowns. There is a TAC 1000 cyanide online analyser which measures and controls cyanide addition. This process control system, in conjunction with oxygen injection, has reduced cyanide consumption.

Elution of the gold from the loaded carbon and subsequent electro-winning is done on site. There are two 2.5 tonne elution columns which operate in parallel. The design of the columns is unique in that the elution and the electro-winning processes take place in the same pressurised vessel. The advantage of this is that there is no circulation of solution outside the vessel which requires heat exchangers for heating and cooling. The overall effect is that the system is very energy efficient and cost effective.

During electrowinning the gold is deposited on wire wool cathodes within the elution column,
and the loaded cathodes are removed on a planned cycle and acid-digested. The resultant gold solids from acid digestion and the re-dressed gold concentrate from Knelson Concentrators are smelted into bars. The granular activated carbon is kiln regenerated before it is recirculated back to the CIL section. Loaded carbon is not acid treated in an attempt to reduce reagent costs. Carbon reactivation has remained acceptable although the acid treatment can be re-introduced if required. The gold bullion, in the form of doré bars, is delivered, as required by Zimbabwean gold-mining law, to the Government-operated Fidelity for samplingand onward delivery to the Zimbabwe gold refinery.