Last time we started to tell you how gold is mined in the Akmola region of Kazakhstan. This time we are going to show how the precious metal is mined in East Kazakhstan by another company and what is needed to get a gold bar with weight of twelve kilograms (26.45 pounds).
As opposed to the place we described last time, here gold is mined underground. The mine was opened in 1786 and gave a name to a small town where miners’ families have already been living for the second century.
According to locals, miners are always easy to recognize – they are terse, straightforward and gloomy. That’s how their profession influences them. Every day a miner stays for hours underground holding a hammer weighing 50 kilograms (110 pounds) in his hands.
It’s not the place for weak people. This work is very hard. Miners’ salaries depend on their skills – from 150 to 280 thousand tenges (1000 – 1900 US dollars).
The mine extracts 2 million 150 thousand tons of ore annually. Normally two grams of gold are found in a ton of ore. The main products of the mine are lead-zinc ore, copper ore, lead-zinc ore with a high content of gold.
Nearby is a dressing mill. Firstly ore is classified and grinded, then it undergoes processes of gravitaion and floatation.
After grinding the ore comes to jigs where the process of gravitation begins.
Classification goes before floatation.
Here the gold-containing foam enriched by minerals is separated to be finally sent to the department of concentration.
Next, upon some technological operations, the grinded ore comes to the gravity table. At this stage gold particles content may reach 100 gram per ton. The yellow particles on the photi above are gold, grey mass is copper.
The result is gold-containing concentrate which is packed into such a container.
The warehouse of the processing plant. Here they store lead, copper, zinc and gold concentrates.
It’s the place where they get high-carat gold and fine silver.
Silver is separated from gold by electrolysis.
Silver is dissolved in nitric acid electrolyte and precipitates in the form of crystals.
Anodic sludge of the silver electrolysis accumulates in bags containing anodes. This sludge contains gold, platinum metals and silver.
These are silver crystals which are to be melted in induction furnaces.
Their temperature is 1200-1400 C.
The metal needs 8-9 hours to cool down.
Marking is made manually.
They indicate a year of manufacture, batch number, ingot number, the country of manufacture (Kazakhstan). There are also an image of a deer and a trademark (boots image). Below is a weight in ounces – 995.9. And the lowest line contains the information about grade, content and weight of silver.
Silver bullion bars. The information about the amount of precious metal produced a year is a commercial secret.
Making gold bullion bars.
And this is the place where finished products are stored. Everything but the bars is forbidden to be shot.
One bar like this weighs about twelve kilograms and costs more than 700 thousand dollars. The bars produced here meet the high quality standards of LBMA (London Bullion Market Association) and have a London Good Delivery status.