Thunderegg Agates are formed within rhyolite volcanic ash layers. They are rough spherical shapes, varying in size from less than an inch to over a metre long. Thundereggs usually contain centres of chalcedony which may have been fractured followed by deposition of agate, jasper or opal, either uniquely or in combination. A unique characteristic that these specimens have is the fact that they often look like ordinary rocks on the outside, but slicing them in half and polishing them may reveal intricate patterns and colours. These particular specimens are examples of thunderegg agates. Agate is a variety of chalcedony, a cryptocrystalline form of quartz. The agate component contributes to the intriguing internal patterns of the specimens. The specific locality of these specimens is unknown but they can be found in flows of rhyolite lava. They are formed in gas pockets in the lava, which act as moulds. These specimens can be found globally, with specific locations in Germany being particularly abundant. 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.Two small solid specimens with pale, sandy-coloured exteriors and fractured internal patterns. burke museum, beechworth, geological, geological specimen, thundereggs, thundereggs agate, agate, rhyolite, rhyolite lava, volcanic ash, chalcedony, cryptocrystalline

Ventifacts are sand-blasted rocks that are typically faceted and often display parallel grooves carved by wind-blown sand. They are useful indicators of wind direction and strength in environments such as deserts, mountains, and coastal areas because they are usually not hidden by later sediment, soil or vegetation cover. In Antarctica ventifaction is strongly related to the composition or type of rock. Ventifacts are important because they provide evidence for abraders such as sand, dust or snow and ice crystals, and offer a unique understanding of past wind processes that are effective in the reconstruction of past wind flow conditions and can provides clues to weather and climate changes in the past. Interestingly ventifacts have also been found on the surface of Mars. They were a threat to the NASA rover due to the sharp angles of the facets, created by the Martian wind over the course of millions of years. These Martian ventifacts act like weathervanes for past wind and weather patterns on the red planet in a similar manner to those found on earth.The Geological Survey of Victoria was instigated in response to the Victorian Gold Rush which began around 1851 in the Beechworth, Castlemaine, Daylesford, Bendigo and Ballarat areas. The survey was conducted by Alfred Richard Cecil Selwyn from his arrival in December 1852 until his resignation in 1869and during this time he trained many notable geologists, e.g. Aplin, Wilkinson, Daintree, who went on to other State survey senior positions. This specimen was among those donated to the Burke Museum in 1868.A hand-sized solid mineral specimen in shades of dark and light browns with light lines visible in all configurations and a groove on configuration 2.light lines visible in all configurations and a groove on configuration 2burke museum, beechworth, geological, geological specimen, ventifact, antarctic region, antarctic, alfred richard cecil selwyn, alfred selwyn, wind direction, wind strength, abraders, wind flow, climate change, reconstruction of wind flow conditions, weather change, mars

Galena is the natural compound of lead and classed as a sulphide, it crystallises in a cubic pattern and its chemical formula is PbS. Galena is a primary source of both lead and silver. This specimen of Galena comes from Broken Hill. Broken Hill has one of the world’s largest and most significant deposit of ore for the production of lead. Mining of Galena at Broken Hill began with the staking of land by Charles Rasp in 1883. By the following year, in 1884, Rasp and six others had formed Broken Hill Mining Company. Broken Hill Mining Company eventually evolved into BHP group limited and is currently the largest mining company in the world and the largest company in Australia. There is archaeological evidence from artefacts discovered in Turkey that humans have been extracting lead from galena by the process of smelting since at least 6500 BCE. This specimen also has quartz on the top surface which is frequently discovered alongside Galena. This mineral specimen is of historic significance as a sample of Galena extracted from Broken Hill during the 19th century. Mining for Galena in Broken Hill begin in 1883 by Charles Rasp and evolved into the world’s largest mining company – BHP Group Limited. Broken Hill is one of the world’s most significant deposits of ore for the production of lead. 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 flat, hand-sized, grey sulphide specimen that is the natural compound of lead with a quartz formation on the top surface. Existing Label: GALENA / (with quartz) / Locality: Broken Hill / N.S.W 120 x 70 x 29geological specimen, geology, geology collection, burke museum, beechworth, galena, galena quartz, quartz, charles rasp, broken hill mining company, bhp group limited, bhp, lead, ore, lead sulphide, sulphide, silver, broken hill

Sphalerite or sphaelerite is named from the Greek word for 'treacherous' or 'deceiver' as specimens can vary widely in appearance, making them hard to visually identify. It is a zinc sulfide with the chemical composition (Zn,Fe)S, the most important ore of zinc. Specimens of sphalerite can contain iron as a substitute for up to 25% of the usual zinc present, as well as trace elements of gallium, cadmium, geranium and indium. Small amounts of arsenic and manganese may also be detected. Sphalerite is found in igneous, sedimentary and metamorphic rocks. It forms when carbonate rock encounters acidic, zinc-bearing fluid. It often forms in veins or in fissures of the existing rock, with colours and crystal shapes dependent on the composition of the the combining elements. It forms isometric crystal shapes including cubes, tetrahedrons, octahedrons, dodecahedrons. This specimen was collected in approximately 1852, in Broken Hill, NSW, as an adjunct to the Geological Survey of Victoria. It was donated to the Museum in 1868. 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 specimen is significant as an 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.A pipe-shaped specimen of sulfide-mineral zinc ore displaying patches of black, brown, beige and gold colouring. The main item has associated broken pieces. geological specimen, geology, geology collection, burke museum, beechworth, mineralogy, indigo shire, geological survey, sphalerite, sphaelerite, zinc ore, broken hill, nsw, victoria, galena, fluorite, chalcopyrite, lead, cadmium, gallium, germanium, indium, iron

This specimen was recovered from Broken Hill, NSW. It was given the name Mangan Hedenbergite in 1819 by Jöns Jakob Berzelius in honor of Mr. Anders Ludvig of Hedenberg who was the first to define hedenbergite as a mineral. Hedenbergite, belongs in the pyroxene group having a monoclinic crystal system. The mineral is extremely rarely found as a pure substance. Mangan Hedenbergite is a manganese bearing variety of Hedenbergite. Manganese is the world’s fourth most used mineral after iron, aluminium, and copper primarily because it has no satisfactory substitute in its major applications. Globally, the steel industry is the primary user of manganese metal, utilizing it as an alloy to enhance the strength and workability of steel and in the manufacture of tin cans. Manganese is a key component of certain widely used aluminium alloys and, in oxide form, dry cell batteries used in electric vehicles. These batteries are in high demand. Another potential use for manganese may as an additive to help coat and protect a car’s engine. Manganese is also used for non-metallurgical purposes such as plant fertilizers, animal feed, and colorants for bricks. 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 hand-sized mineral specimen in shades of silver and blackmanganese, open cut mine, manganese ore processing, bell bay, tasmania, northern territory, steel industry, zinc-carbon batteries, alkaline batteries, tin cans

Pyrite also known as iron Pyrite or fools gold is an iron sulfide with a chemical formula of FeS2 and is the most abundant sulfide mineral. Its metallic luster and pale brass-yellow hue give it a superficial resemblance to gold for which its nickname of Fools Gold comes from. There are a number of iron pyrite mines in Victoria and many would have been mined during Victoria's Gold Rush revolution in the 19th century. As it's lustrius yellow metallic look closely resembles gold, it is likely that it was often mistaken for gold as real gold was also often found in similar metamorphic and sedimentary rock. 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 collections were collected in Victoria as part of the Geological Survey of Victoria that begun in 1852 (in response to the Gold Rush). Collecting these specimens was an important part of Australia's early Geoplogical scientific discovery for mapping the earth's surface. It is unknown where in Victoria this specimen was mined from however; it shows strong provenance connections to Victoria's gold mining history and represents through larger economic and cultural structures the impact the Gold Rush had on Victoria during the 19th century. A solid coin-sized Pyrite crystal in black slate in shades of beige with tiny crystal structures. Pyrite / crystals / BB / in black slate / probably / victoria / (nice specimen)geology, geological specimen

Azurite is a secondary copper mineral made by the weathering of copper sulphide ore deposits. Azurite is formed from copper, carbon, oxygen and hydrogen. There are over 45 forms of azurite that are more well-known, however over 100 forms have been found. Azurite is also commonly found together with Malachite, and Azurite is often psuedomorphed to Malachite. This specimen was found at the Great Cobar Copper Mine in New South Wales, which was founded in 1870. At the time it was one of the largest mining operations in the world. It was the largest copper mine in Australia and housed the southern hemisphere’s tallest chimney stack. The international price of copper collapsed at the end of World War 1 which led to the closure of the Great Cobar Mine on March 16th 1919. A year later on March 10th 1920 an underground fire in the CSA (Cornish, Scottish, Australian) mine started and burned for 16 years. The closure of the mine and the fire left thousands jobless and many people left the area. These were factors in Cobar facing a long stretch of poverty, until a boom in the 1960s led to the reopening of the mine. The mine still operates today, obtained by Metals Acquisition Limited in June 2023. Azurite is considered an uncommon mineral. Named for its deep blue colour, azurite was historically used for pigment making and as a gemstone, despite its softness. This specimen was donated to the Burke Museum between 1868-1880 as part of a larger collection of geological and mineral specimens. Many of the specimens in this collection were obtained as part of the Geological Survey of Victoria, which started in 1852. The Survey aimed to map the scientific makeup of the earth.A solid copper mineral with shades of darker blues almost covering it.burke museum, beechworth, indigo shire, beechworth museum, geological, geological specimen, mineralogy, cobar mines, great cobar copper mine, cobar mining, new south wales, azurite, azurite specimen

Quartz is one of the most common minerals in the world. It is formed by a 3d structure of silicon and oxygen. While it is a simple mineral, it can come in a variety of shapes and colours. When quartz is pure it is colourless, transparent and can appear glass-like. Better known and more rare variations of quartz include amethyst and smoky quartz. This specimen is a vein of quartz in Breccia Conglomerate. Breccia is coarse-grained clastic rock which is made up of broken rock fragments and held together by mineral cement. The locality of this specimen is unknown. While quartz is a very common mineral and does not have rarity, it is an important material in industrial settings. One of it's physical and chemical properties is that it is piezoelectric, which means it can be used to generate an electric charge. This has made it useful in the manufacturing of timekeeping devices. This specimen was donated to the Burke Museum between 1868-1880 among a larger collection of geological specimens. It was collected as part of the Geological Survey of Victoria which begun in 1852 as a response to the Gold Rush. Collections were distributed to organisations across Australia to encourage the further study of the scientific makeup of the Earth. A solid egg-shaped rock with a mineral vein forming a ring around the rock in shades of brown and beige.burke museum, beechworth, indigo shire, beechworth museum, geological, geological specimen, 1852 geological survey of victoria, mineralogy, quartz, breccia, breccia conglomerate, conglomerate

Feldspar, derived from the German word feldspat, is a group of minerals which is the most common mineral group found on Earth, making up more than half of the planet's crust. The major rock-forming minerals in the Feldspar group include albite, anorthite, orthoclase and microcline. (Mindat, Feldspar Group). Orthoclase is part of the Feldspar Group subgroup, Alkaline Feldspar, which are known to be poor in calcium, and mostly rich in potassium. It is further also considered to be a K Feldspar, a subgroup of Alkaline Feldspar that are Potassium-dominant with variable crystal symmetry and Al-Si ordering state. Orthoclase are most commonly Colorless to white, Greenish white, Grayish yellow, or Pale pink and transparent to translucent with slightly pearly cleavage. The mineral rates at a 6 on the Mohs Hardness Scale. (cannot be scratched with a knife, but scratches glass with difficulty). The stronger green colour of this particular specimen is distinctive to the Broken Hill region (where it was found), and due to a small amount of lead. (BB) Its qualities find it misidentified at times as as microcline variety amazonite. Broken Hill is one of the world’s richest lead-zinc-silver deposits. The huge, 300-million-tonne orebody was discovered in 1883 and the superb mineral specimens attract collectors from around the world. (Australian Museum, Minerals from Australia: Australian mining regions)While feldspar is not by any means rare, this particular specimen has qualities distinctive to the Broken Hill mining district, with these properties leading at times to the mineral's misidentification. This creates potential for further study and identification of these mineral deposits through methods such as microscopic twinning, or using the position of certain d values in XRD patterns to calculate the degree of disorder of a K-feldspar, as discussed on the Mindat website (Mindat.com, Orthoclase:About Orthoclase). 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 small aluminosilicate mineral composition which is primarily pale green and blue-grey in colour with traces of beige and white throughout. Note: green plumbian orthoclase (aka green feldspar) is an indicator mineral for the Broken Hill style lead-zinc deposits.N/Abroken hill mine, geological specimen, minerology

This specimen was donated in 1868 by Alfred Selwyn. Olivine is typically found in basic and ultra-basic igneous rocks around the world, in a variety of colours including yellowish green, olive green, greenish black and reddish brown with a transparent to translucent diaphaneity. The luster of the specimen is vitreous, the luminescence non-fluorescent and when fractured the mineral is very brittle producing small, conchoidal fragments. Chromian diopside is normally found in small sizes as the larger the size of the mineral the darker the colour is, almost black rather than green. Chromium is the element that gives chromian diopside and emeralds their rich green colour. Diopside is found across the world in multiple colours however gem-quality chromian diopside is mined in Siberia, Russia and prominent within the jewellery industry as a more affordable substitute to emeralds. Chromium-bearing diopside has been located across Australia. Chromium-bearing Diopside is located across the world found in North America, parts of South America, and across Australia, Africa, Europe and Asia. Chromium-bearing Diopside is mined in Siberia, Russia and is sold as a commercial substitute for emeralds. The stone is often turned into jewellery. This item is one of many geological and mineral specimens that constitute a broader collection obtained from various regions across Australia (as well as some international locales) and generously contributed to the Burke Museum between 1868 and 1880. A significant portion of these specimens originated from Victoria and were acquired as a result of the Geological Survey of Victoria, initiated in 1852 during the Gold Rush era. The primary objective of this survey was to investigate and chart the geological characteristics of Victoria. The procurement of geological specimens played a vital role in advancing our comprehension of the Earth's scientific composition and was instrumental in supporting research and educational institutions throughout Australia, including the Burke Museum, in their efforts to foster further exploration and study. A solid mineral specimen in shades of green, grey and brownburke museum, beechworth, geological, geological specimen