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The Beechworth Burke Museum
Geological specimen - Smoky quartz crystals, unknown
Quartz is an extremely common mineral to find across the world. Quartz can have two forms; Microcrystalline quartz or Crystalline quartz. Microcrystalline quartz is a fine grain quartz where crystalline quartz is often a large crystal. This specimen is a crystalline quartz. Made of silicon oxide, this specimen is called smokey quartz crystals because of its brownish colour. However, the colour of quartz can vary. In addition, quartz are formed in deep-seated igneous rocks and crystallized through hot aqueous solutions. This type of crystal can be found all over Australia, including Beechworth in Victoria. Other places quartz can be found is the Ashburton River area in Western Australia, Marlborough in Queensland, the Lune River area in Tasmania and Kingsgate in New South Wales. This specimen is significant because it is common to find this kind of mineral. While the location of where this specimen was originally from is unknown, it highlights the many places in Australia where quartz is found. It demonstrates that quartz makes up a large portion of Australia's geology. In addition, quartz itself can vary in its colour and shape. This specimen represents one of these variations. That being smoky quartz crystals. 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 large hand-sized quartz mineral with shades of brown and gray throughout.Smoky quartz / crystals /locality/ unknown / (needs a wash) /BBgeological specimen, geology, geology collection, burke museum, beechworth, microcrystalline, quartz, quartz mining, quartz reefs beechworth, smokey quartz crystals, crystals, crystalline, silicon oxide, brown, colour, igneous rocks, magma, ashburton river, western australia, marlborough, queensland, lune river, tasmania, kingsgate, new south wales, nsw -
The Beechworth Burke Museum
Geological specimen - Agate and Quartz pebbles
Agate occurs when amygdales (gas pockets) form in the upper levels of basaltic lava flows. If these pockets or bubbles are iniltrated by water bearing silica in solution, the fluid dries and hardens in layers, forming round or egg shaped nodules or geodes within the rocky matrix. Agate is formed of a silica mineral chalcedony similar to quartz. Although relatively common and semi-precious, agate has been prized since at least 1450 BC - an intricately carved agate seal was found in the 2015 excavation of a grave belonging to a Mycenaeum priest or warrior near Pylos in Greece. Agate is also used in jewellery and other decorative or ritual purposes due to its often striking appearance. Quartz is found all over Australia, including Beechworth in Victoria. It is formed in deep-seated igneous rocks and crystallized through hot aqueous solutions. It can have two forms; Microcrystalline quartz or Crystalline quartz. Microcrystalline quartz is a fine grain quartz where crystalline quartz is often a large crystal. The colour of quartz can vary. These specimens were collected in Victoria in the vicinity of the Burke Museum. Victoria and other regions of Australia were surveyed for sites of potential mineral wealth throughout the 19th Century. The identification of sites containing valuable commodities such as gold, iron ore and gemstones in a locality had the potential to shape the development and history of communities and industries in the area. The discovery of gold in Victoria, for instance, had a significant influence on the development of the area now known as 'the goldfields', including Beechworth; the city of Melbourne and Victoria as a whole.The specimens are significant as examples of surveying activity undertaken to assess and direct the development of the mineral resource industries in Victoria and Australia, as well as the movement to expand human knowledge of earth sciences such as mineralogy and geology in the nineteenth century.Geological specimens of Agate and Quartz respectively; the fist-sized piece of Agate has peach/coral colouring with grey concentric patterning and the smaller piece of quartz is a uniform yellow/orange shade. Existing label: Local pebbles / (agate and / quartz / (yellowish) / egg-shaped). / BB geological specimen, geology, geology collection, burke museum, beechworth, agate, quartz, north-east victoria, indigo shire, geological surveys -
The Beechworth Burke Museum
Geological specimen - Ribbonstone-banded Chert
Chert is a sedimentary rock composed of microcrystalline or cryptocrystalline quartz. While usually biological in origin, chert may also occur as a chemical precipitate or a diagenetic replacement--the product of petrified trees. Chert, also known as flint, was a common tool for early peoples during the stone age. It forms in limestone and chalk sediments as silicon dioxide microcrystals which grow into nodules of chert. Chert is found in many mines across the Northern Territory, however this specimen is sourced from the Mount Todd gold mine in Katherine. Its use in weaponry, both during the Stone Age and during the 18th century. Chert produces a spark when struck against steel, meaning t hat it can be used to start fires and fire guns. Chert was thus used in flintlock firearms, in which the gunpowder is ignited by a flint hammer striking a steel plate. Chert was commonly used in the Stone Age as a result of conchoidal fracturing causing very sharp edges, allowing early peoples to fashion weapons and cutting tools. It also rates a 7 on the Mohs Scale, making it a very hard and durable stone that maintains its sharpness. As a result, the significance of chert as a signifier of early indigenous Australian life makes this specimen important. It is also known that chert is a valuable mineral that was used as a trading commodity. Chert has also been valuable during the 1700s, proving itself to a be an important historical specimen in matters of war. A solid silicon dioxide mineral in shades of brown, white, and beigeburke museum, northern territory, chert, flint, minerals, geological specimen, katherine, mount todd gold mine, katherine northern territory