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

Coloured map of the world on blue including the words for the "Lest We Forget" lament. The Moor-Rul Viewing Platform, part of the Kangaroo Ground War Memorial Park opened in April 2007. Eight double-sided interpretation panels on the Moor-rul viewing platform highlight the area's Aboriginal and European history of the area and also details of local geology, flora and fauna. These panels feature high quality graphic design and professionally written text. The subjects covered are: ''Womin Je Ka" Welcome The Kulin Nation Singing, Dancing, Ceremony, Celebration This Country, My Home The Highland Taken Auld Lang Syne "Same Land Different Views" Working the Land Food from the Earth or "Earth's Harvest" Lest We Forget, "And with the going down of the Sun .... (3 panels) This Black Earth Those other indigenous inhabitants - Kangaroo Ground's Wildlife Silent Witnesses - Kangaroo Ground's White Manna Gums Belonging A Place of Reverence and A Tower of Strength Souce: EDHS Newsletter No 173 March 2007. As part of a program to acknowledge the Anzac Centenary Nillumbik Shire Council partnered with Yarra Plenty Regional Library to provide a bus tour with commentary of local sites of significance: Shire of Nillumbik World War One Memorials tour, 10 August 2016. These included Eltham township, the Shire of Eltham War Memorial at Kangaroo Ground, Christmas Hills war memorial, Hurstbridge memorial recreation park and finshed at Eltham Library to view the Writing the War exhibtion at Eltham Library Community Gallery. Born Digitalworld war 1, war memorials, shire of nillumbik, moor-rul viewing platform, kangaroo ground, shire of eltham war memorial, interpretative signage, interpretation panel, map, display panel

This mineral is commonly found in caves. The term 'Dogtooth Spar' refers to the crystal-like structure within the mineral which is grown in calcite-rich water, thus forming calcite crystals. The environments necessary for these crystals to form is commonly within the water within caves, which are consistently supplied with calcium over a long period of time. It is also known as a scalenohedral crystal.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 mineral calcite, with a grey base and white crystal structures emerging upwards from the base.dogtooth spar, scalenohedral crystal