A range of coloured stones from the Argyle mine, Western Australia, Australia
For every one million carats of diamond produced at Argyle, only one carat will be of high quality pink colour.
Image: Ben Healley
Source: Museum Victoria
Diamonds, Argyle mine, Western Australia, Australia
Flaws and inclusions affect the clarity of a diamond. Industrial diamonds are opaque while high-quality gems are free of imperfections.
Image: Ben Healley
Source: Museum Victoria
Diamond, Argyle mine, Western Australia, Australia
Large diamonds are rare. This 41.7 carat stone was found in April 1997 and is the second-largest diamond from the Argyle mine (the largest weighs 47.2 carats). This stone has an unusual crystal shape quite different to the common octahedral form. The crystal contains some small black inclusions.
Image: Benjamin Healley
Source: Museum Victoria
Diamonds, Argyle mine, Western Australia, Australia
This 'run-of-the-mine' sample contains about 890 carats of rough diamonds, less than two carats each in weight, in various grades.
Image: Ben Healley
Source: Museum Victoria
Diamonds, Argyle mine, Western Australia, Australia
Diamond is made of carbon. When pure it is colourless but trace amounts of other elements adds colour. Nitrogen, results in yellowish diamonds, and boron blue. Imperfections in the crystal structure also affect the colour and may be responsible for the brown (‘champagne and cognac’) and pink diamonds at Argyle.
Image: Ben Healley
Source: Museum Victoria
Diamonds, Argyle mine, Western Australia, Australia
Diamonds form a variety of crystal shapes. The classic diamond shape (octahedron) is the most common.
Image: Ben Healley
Source: Museum Victoria
Diamond is a form of crystalline carbon and is the hardest mineral on Earth. Diamonds crystallise in the mantle and are brought rapidly to the surface by volcanic eruptions. An old volcanic ‘pipe’ at Argyle in Western Australia provides unusual champagne (pink to brownish) gem diamonds. The ‘four Cs’ – carat, colour, clarity and cut – determine the value of a stone.
The Argyle Diamond Mine, in the East Kimberley region of Western Australia, is one of the world's largest diamond producers. The deposit was discovered in 1979 and mining commenced in 1983. About 5% of diamonds produced by Argyle are high-quality gem, 70% are near gem and 25% are industrial grade.