Selwynite is a fine-grained, compact green rock made primarily of chromian muscovite (fuchsite) and diaspore. Corundum and fuchsite can occur together in the form of massive aggregates or nodules. Often, copper carbonates are found as earthy films or tiny crystals in joint planes. The mineral name honours the late A. R. C. Selwyn, founding Director of the Geological Survey of Victoria. The particular specimen, a mottled green stone suitable for carving was recovered and found in Heathcote, Victoria, Australia. The rarity and qualities of this mineral attracted commercial mining, which was not successful, but traces of the mine shafts still exist today, and it is still highly valued by mineral collectors.Selwynit is considered to be one of the rare forms of rock because it is composed of phosphate minerals containing zirconium. This is an extremely rare combination found in nature. 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 fine grained rock composed of mainly of chromian muscovite (fuchsite) diaspore and corundum.geological specimen, geology, geology collection, burke museum, beechworth, mineralogy, heathcote, mineral collectors, selwynite, green rock, rock specimen

Tourmaline is a group of minerals belonging to the complex borosilicate mineral class. These minerals are known for their striking and varied colours, making them prized gemstones. Tourmaline crystals can come in various shades, including pink, green, blue, brown, black, and colourless. They are often transparent or translucent. Tourmaline's chemical composition is complex, but it typically includes elements such as aluminium, iron, magnesium, sodium, lithium, and potassium. The specific arrangement of these elements in the crystal lattice gives rise to the different colours and properties of tourmaline specimens. Tourmaline specimens from Beechworth, Victoria, Australia, are a notable part of the region's mineral heritage. These tourmalines are of interest to mineral collectors and enthusiasts. While the tourmaline found in Beechworth is not as well-known as some other tourmaline varieties, it has unique characteristics and a historical context associated with the gold mining areas in Beechworth.The significance of tourmaline in Beechworth, Victoria, Australia, lies in its unique geological and historical context, contributing to both scientific and cultural aspects. The tourmaline mined in Beechworth is a rare and unique variety of tourmaline that is primarily found in the historic gold mining areas surrounding Beechworth. Its occurrence is closely linked to the geological processes that shaped the region during the Gold Rush era. The discovery of tourmaline in Beechworth adds to the rich mineral heritage of the area, which was historically known for gold mining. The specimens serve as a tangible connection to the region's mining history and contribute to preserving its geological legacy. The presence of tourmaline in Beechworth showcases the mineralogical diversity of the area. Tourmaline is known for its wide range of colours and unique properties, making it a valuable subject of study for mineralogists and geologists. Tourmaline specimens from Beechworth have educational significance, providing opportunities for research and study. They offer insights into the geological processes and mineral formation in the region, contributing to a better understanding of Earth's geological history.A hand-sized solid mineral specimen in shades of brown, green, light grey and dark greyTOURMALINE (schorl) / (Silicate of boron and aluminum) burke museum, beechworth, indigo shire, geological, geological specimen, mineralogy, tourmaline

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

Named in 1845 by Wilhelm Karl von Haidinger cerussite takes its name from the Latin cerussa, meaning 'white lead'. When viewed under certain lighting conditions cerussite gives of fire and rainbow-like colours (due to its high dispersion) and it is quite sought after by geological collectors for this very reason. Cerussite is usually found in the oxidised zone of lead ore deposits. It is a very common weathering product of galena and other lead ore minerals. It is a secondary mineral, meaning it forms as a result of the alteration of pre-existing minerals in the Earth’s crust. The presence of lead in cerussite makes it potentially toxic. Historically, it has been an important source of lead, which has numerous industrial applications, including in batteries, construction materials, and radiation shielding. Cerussite has a crystal structure that belongs to the orthorhombic crystal system. Its crystal structure is characterized by a three-dimensional arrangement of atoms in a repeating pattern. The crystal lattice of cerussite consists of interconnected lead (Pb) and carbonate (CO3) ions. This crystal structure is visible in the specimen. This specimen was found in Dundas (formerly Mount Dundas), a historical mining locality, mineral field and railway located on the western foothills of the West Coast Range in Western Tasmania. During the 1890s Dundas swelled in numbers however it is now lost in a temperate rainforest and its population is now 2. The present Dundas Extended mine, about 1.5 km east of Dundas is presently worked for specimen material.Faceted cerussite gems are considered rare and valuable, given the softness of the mineral. This item is not a faceted gem however its historical and scientific research potential give it significance; mined in an Australian township, this cerussite could shed light on the now lost history of Dundas and the mining that occurred there. Additionally, the uses of this mineral in historical industrial processes give it scientific significance. Such knowledge can add to understandings of the geographical and geological nature of Western Tasmania and allow for further study of Australian geological specimens. A small lead carbonite mineral with shades of cream, white and brown throughout, flaky shards of white at base. CERUSSITE / (lead carbonite) / Locality: Dundas, W. Tasmaniadundas, tasmania, cerussite, lead, orthorhombic, geology, minerals, mining