Diamond Mining in Australia
The first diamond exploration in Australia dates back to the year 1851, in New South Wales. A large quantity of diamonds were also mined in Copeton and Bingara from 1867 to 1922. However the mining was again resumed from 1997. There have been many instances of diamond mining in Australia across other landscapes as well.
Most Australian diamonds are excavated from the Argyle deposits. This accounts for the major part of diamond production in Australia. A small amount of alluvial diamonds are excavated from Smoke Creek and Bow River mine. However higher quality gems have been found in Merlin in the Northern Territory. May explorations carried out during the 1970’s led to the founding of low quality gem pipelines. In the 1980’s shark cages were used to protect scuba divers from crocodiles, while they searched for diamonds.
The Argyle diamond resource makes up for the large number of the world’s diamond resources, these diamonds have the highest diamond grade in the world. 100% of the product found at Argyle is sold directly to the world market. The most famous of these are the renowned pink diamonds of Argyle. These are polished in the factory at Perth.
The mining and processing of Australian Diamonds
- Initially open pit mining was used for the extraction of diamond ore in Argyle. A large scale block operation is now carried out in the mine. The broken ore is then crushed and later rotated in drums called scrubbers which filter out diamonds.
- Any diamonds bigger than 18mm in diameter would be crushed. However their extraction is pretty uneconomical because they are often low quality.
- The alluvial deposits at smoke creek and Bow River are strip mined making use of excavators. These are then sent directly to a processing plant where these are screened for better quality diamonds.
- Sieving can help separate 15 different sizes of diamonds. There are highly skilled sorters which grade these diamonds into seven thousand categories. These are graded according to their crystalline shape, size, color and quality. The best diamonds are considered as gems and the poor ones are put to industrial use.
- Rough diamonds are cut and polished by splitting through its grain. This helps in removing the impurities.
- Diamonds are then put through laser blades which help saw the grain across through the diamond. The diamond which is sieved resembles the shape of a top.
- These diamonds are then further polished and shaped with the help of a metal grinder. Brilliance is only achieved when the facets of diamonds are the right size and the angles complement each other. These cut diamonds are then graded according to their cute, color and quality.
- Roughly you can expect to lose 50% of the diamond in the cutting polishing process. The Cullinan diamond excavated in South Africa produced some one hundred and five diamonds.
Uses of diamonds
- Diamonds have been used since time immemorial. They represent talismans of beauty and wonder. These are used in jewelry and are a firm favorite with women.
- Besides being used for adorning jewels diamonds are put to industrial use as well. Diamond machines tools are used in electrical and engineering industries.