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The Beechworth Burke Museum
Geological specimen - Chalcopyrite
... mohs scale.... Chalcopyrite has a hardness of 3.5-4 on the Mohs Scale. It is a member... fools gold mohs scale crystals minerals historical geological ...This specimen originated from Mount Lyell on the west coast of Tasmania, where a large group of open cut and underground copper-silver-gold mines began operating in 1883. Between 1893-1994, the Mt Lyell Mining and Railway Company were responsible for operations. The Mt Lyell copper-gold mines produce some excellent crystallised specimens of chalcopyrite and other minerals. The deposits are generally considered to be of Cambrian volcanic origin, but there are indications of Devonian granitic influence on the ores, plus local remobilisation during Devonian deformation. Over 120 million tonnes of ore was produced from several workings, including the main Prince Lyell mine and the North Lyell mine, which was also of great importance. The Mount Lyell mines have a long history of human and environmental disasters, including the 1912 North Lyell fire that killed 42 miners, and two separate incidents in 2013 in which three people lost their lives. The environmental impacts from this complex of mines are extensive, with waste tailings and heavy metal contamination flowing directly into the King and Queen River catchments. In 1954, the eminent Australian historian, Geoffrey Blainey, published 'The Peaks of Lyell' which delves into the history of the 1912 North Mount Lyell Disaster.Chalcopyrite does not contain the most copper in its structure relative to other minerals, but it is the most important copper ore since it can be found in many localities and occurs in a variety of ore types. The brassy-yellow colours in Chalcopyrite mean it is often confused with pyrites and gold, leading to use of the term, "fool's gold." Chalcopyrite has been the primary ore of copper since smelting began five thousand years ago. 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.This hand sized solid mineral specimen has shades of brass-yellow with spots of iridescent green-black tarnish. Chalcopyrite is a copper iron sulphide mineral and a major ore of copper common in sulphide veins and disseminated in igneous rocks. Chalcopyrite has a hardness of 3.5-4 on the Mohs Scale. It is a member of the tetragonal crystal system and has metallic lustre and opaque transparency.burke museum, beechworth, indigo shire, beechworth museum, geology, geological specimen, chalcopyrite, copper pyrites, copper mining, tasmanian geology, mount lyell, mount lyell mines, fools gold, mohs scale, crystals, minerals, historical geological collection, victorian geological survey, a.r.c selwyn, gold rush, van diemans land -
The Beechworth Burke Museum
Geological specimen - Common Opal, Unknown
... and is typically opaque. It scores high on the Mohs hardness scale... and is typically opaque. It scores high on the Mohs hardness scale ...It is not known where this opal originated. Common Opal is formed from silica-rich water entering the earths crust and hardening into a gel of water and silica-spheres, layered through the specimen. Common opal differs from precious opal in colouration and appearance, with precious opal including more colours, and having a translucent or glossy appearance, where common opal shows less colour and is typically opaque. It scores high on the Mohs hardness scale, and is common throughout the world, especially in Australia, where it is far more prevalent than the highly-prized precious opal. Australia is also the highest producer of opals in the modern world. 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.A solid, silica-based mineral specimen of Common Opal in shades of grey, green, and yellow, with a thick grey vein running through the centre. geological specimen, geology, geology collection, burke museum, beechworth, opal, common opal, gemstone, mining -
The Beechworth Burke Museum
Geological specimen - Fluorite (purple)
... a high level of lustre, the mineral is very soft (4 on MOHS... a high level of lustre, the mineral is very soft (4 on MOHS ...Fluorite comes in a variety of natural colours and crystal formations and glows under ultraviolet light (the word 'fluorescence' comes from the same etymological source). In its pure form, calcium fluoride, it is a colourless combination of the elements calcium and fluorine, but gains its colour from trace elements that infiltrate or replace calcium within its crystal structure during its formation. Although fluorite crystals polish well and can achieve a high level of lustre, the mineral is very soft (4 on MOHS hardness scale) so it is unsuitable for use in rings and must be handled and stored carefully if used in other forms of jewellery. Most crystals of the mineral are too coarse for decorative purposes but have been mined under the name fluorspar for a variety of commercial and industrial purposes. These include the production of hydrofluoric acid, smelting metal alloys, producing glazes and ceramic finishes and use in medical and dental products. An existing label for this specimen indicates that its origin or collection-point was 'probably USA.' Fluorspar, the form of fluorite used commercially and industrially, was mined in significant quantities in the counties of Hardin and Pope in South-Eastern Illinois throughout the Nineteenth and Twentieth Centuries. Fluorite was made Illinois' state mineral in recognition of its contribution to the state's identity and economy. The specimens are significant as examples of surveying activity undertaken to assess and direct the development of the mineral resource industries, as well as the movement to expand human knowledge of earth sciences such as mineralogy and geology in the nineteenth century.The specimen is a piece of purple shaded fluorite (also known as fluorspar), the mineral form of calcium fluoride. The unpolished specimen presents a dark purple interior with a substantial dark grey crust representing the matrix from which the specimen was obtained. Existing label: Flourite / (purple) / probably / USA / BB /burke museum, beechworth, geological, geological specimen, fluorite, flourite, calcium fluoride, hydrofluoric acid, jewellery, indigo shire, north-east victoria, mining, illinois, usa, united states, fluorine, gemstones, purple stones