Historical information

This specimen was recovered from Mica Schist, Canada. Chalcopyrite is a copper iron sulfide mineral with a chemical composition of CuFeS2. Its name derives from the Greek words for copper (chalco-) and brass (pyrite). It can be found in shades of yellow, green and grey, and, when exposed to acid, it can change to purple, blue, violet and yellow tones. Weathering can cause loss of its metallic luster and its brass-yellow colour. Chalcopyrite forms under various conditions, with the most significant deposits being hydrothermal in their origin. It is known globally as the most important ore of copper for thousands of years, and is thus considered a very important mineral formation.

Given its golden appearance, it is often confused for the mineral gold, earning it the popular reputation as 'fool's gold' or 'yellow copper'. However, it can be straightforwardly distinguished from gold; the latter is soft, with higher specific gravity and a yellow streak, whereas chalcopyrite is brittle, easily scratched by a nail, and has a greenish grey streak. Copper was the first metal that was used by people. It was discovered by the Neolithic man about 9,000 years ago and it gradually replaced stone as it was easier to be shaped. In Australia, search for copper began after the European settlement, leading to the discovery of substantial deposits, like the one at the Olympic Dam in South Australia, which is regarded as one of the largest copper deposits in the world.

Significance

Chalcopyrite has been used for copper since smelting processes began approximately five thousand years ago. Although by no means rare, this the specimen of this mineral can be used to reflect a wider history of industrial uses of copper for a significant portion of human history.

This specimen is part of a larger collection of geological and mineral specimens collected from around Australia (and some parts of the world) and donated to the Burke Museum between 1868-1880. A large percentage of these specimens were collected in Victoria as part of the Geological Survey of Victoria that begun in 1852 (in response to the Gold Rush) to study and map the geology of Victoria. Collecting geological specimens was an important part of mapping and understanding the scientific makeup of the earth. Many of these specimens were sent to research and collecting organisations across Australia, including the Burke Museum, to educate and encourage further study.

Physical description

A solid hand-sized copper iron sulfide mineral of brass yellow, often with an iridescent tarnish, with greenish-black streak and submetallic luster.

Chalcopyrite can be formed in several ways, including crystalizing from accessory minerals in igneous rocks, or from magma or within volcano sulfide deposits. Most commonly, chalcopyrite are found in hydrothermal conditions, where it forms in hydrothermal veins. As a member of the tetragonal crystal system, it often takes the shape of tetra-headed crystals, often with striations along the sides of the crystals.

Inscriptions & markings

#18 Copper pyrites/(chalcopyrite) in/Laurentian Slate/(page 315 of inventory)/page missing from/descriptive catalogue/

Other label:
81 /