Bornite

Bornite (sometimes known as peacock ore) is a sulfide mineral that crystallizes within the orthorhombic system. The minerals most striking feature is its vibrant iridescent blue, purple or cerise colouration which is what appears to attract many eyes initially. Its next surprising (to many) feature is its density, for its size, bornite is very heavy, and those (especially who are just being introduced to geology or mineralogy or who are just viewing it in a show room) often remark at its surprising weight when initially picking it up. Bornite also has a metallic lustre, mainly due to the amount of copper present as it is also a primary copper ore mineral. The combination of Iron & Copper make this a dense mineral, specific gravity 5.06 – 5.08 and is often important in educational establishments. However, it also has a niche in the gemstone gift market, partly due to its bright colour but also when treated with acid, the mineral can change to an even more vibrant blue colour, a bright purple or a brassy yellow a metallic green as well as a mixture of all 4. When subject to this process, the mineral is often sold on as ‘peacock ore’. These mineral samples come from the Congo and are available in various sizes, each supplied in a labelled card tray.