Aurora Acquisition Corp (AURC)

[MUSHROOMKING]

THE RUSSIAN GOLD INDUSTRY

Ore Gold Extraction Process

The ore extraction process comprises the following operations:

Breaking of underground-extracted base ore –300 mm with check screening – 20 mm;
Secondary crushing of the ore –100 mm in the open cycle;
X-ray radiometrical separation of crushed ore (-20 mm.) to derive 30% of non-marketable ore with dump gold content;
1st phase of ore grinding –20 mm to derive a 35% class –0.074 mm.;
Mill discharge jigging, with undersize concentrate sent to gravity separation and take off product sent to further grinding in a closed cycle;
Concentration of undersize product of jigging on tables with the cleaning of table concentrate;
Grinding of the «gold head» with two subsequent cleaning thereof and tailings sent to cyanidation;
Electric-magnetic separation of the «gold head» in order to remove magnetic minerals and instrumentation metal with the latter sent to cyanidation;
Drying of the demagnetized «gold head»;
Magneto-hydrodynamic or ferro-hydrostatic separation of the «gold head» to derive test gold, magnetics and two floats;
Burning (drying) of the MHD-separation concentrate;
Melting to derive the Dore alloy.
The commercial output – base gold in bullion made to TU (specifications) 117-2-7-75 – will be sipped to a gold refinery enterprise.

Placer Gold Extraction Process

Placer gold is mined by the open pit method which includes as follows:

Development operations;
Overburden mining;
Gold-washing (gold sand which is the natural raw material);
Concentration using instruments as may be required by the deposit specifics ( PBSH-1000, PTSH-75), which should have deep and small concentration strakes and add-on devices to extract fine gold;
Manufacturing 99.8% purity bullions.
Processing of Technogenic Materials

For mill tailings, dumps of out of balance and non-standard ores, cakes and cynders the heap leaching method will be the most feasible. The experience of gold extraction from objects with such metal content by using the heap leaching method is available in the Russian Federation as well as abroad.

The initial phase includes crushing to class –5 (-10) mm., and pelletizing the tailings and cynders up to the same size. Then the materials will be stockpiled on a specially prepared damp-proof base and sprinkled. The final phase consists of productive solution collection, gold precipitation and manufacturing of base gold bullion.

An up-to-date method of gold extraction from dumps is the cyanidation by leakage. The cycle lasts 4 to 6 days. During this period 92.1% of gold can be extracted from the solution.