DEPOSIT TYPES
The Blanket orebodies comprise up to 10% of precious metals. The Blanket mineralisation is hydrothermally emplaced and associated with the regionally developed D2 deformation characterised by areas of high strain wrapping around relatively undeformed remnants of the original basaltic flows. Wider orebodies occur within the more ductile tensional high strain areas. Two main types of mineralisation are recognised at Blanket, namely Disseminated Sulphide Reefs (DSR) and quartz-filled reefs and shears. A third type of mineralisation may be evidenced in the form of auriferous sulphide minerals as a replacement of the iron-rich minerals along the hinges of the folds in BIF.

MINERALISATION
Mining at Blanket occurs over a 3 km strike that includes from north to south, the deposits of Lima, Eroica, Sheet, AR Main, AR South, Feudal, Blanket Section (Blanket 1 to Blanket 6) and Jethro. The main Blanket underground workings are connected to Lima by a 2 km long haulage which follows the strike of the main fabric.

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. Gold is deposited at crustal levels within and near the brittle-ductile transition zone at:-
• depths of between 6 km and 12 km;
• pressures between 1 and 3 kilobars; and
• temperatures between 200ºC and 400ºC.

The ........

Blanket Mine uses two mining methods which are well suited to the nature of the greenstone belt deposits. The orebodies range from generally steeply dipping sheet-like deposits of a few meters in width, to pipeshaped and massive deposits with widths more than 50 m. The general practice on Blanket Mine is to implement one of two tailored mining methods, determined mainly by the width of the mineral deposit.

The two mining methods utilised are:-
• Long-hole stoping in wider mineral deposits (orebody widths generally more than 3 m); and
• Underhand stoping in narrow mineral deposits (orebody widths generally less than 3 m).

LONG-HOLE STOPING
Blanket mine uses long-hole stoping in the orebodies with a width greater than 3 m.

To access the orebody, crosscuts are developed from the tramming haulage to the extraction haulage which is located approximately 15 m from the orebody. Drawpoint crosscuts are developed at 15 m intervals along the extraction haulage which provide access to the drawpoints. A twin raise system is developed upwards to establish a sliping point for the development of the sub-drive. One raise serves as an access raise, while the other serves as an orepass to handle ore from the sub-drive development. The twin raise system is developed from one sub-drive to the next for the entire 120 m lift.

Drawpoint raises are established at 15 m intervals along the width of the orebody. A lead angle of 45 degrees is al ........

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