This specimen was found in Harcourt, Victoria. Harcourt is a small historic gold rush town located in a valley at the foot of Mount Alexander (741 m) in the Central Highlands of Victoria. In recent times the goldrush origins of the town have been replaced by a district known for apples, cider and wine. The Traditional owners of Harcourt are The Dja Dja Wurrung people. Granodiorite is a coarse-grained intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. Granodiorite has greater than 20% quartz by volume, and between 65% and 90% of the feldspar is plagioclase. This piece is of significance due to its provenance in Harcourt, Vic. Granodiorite is commonly produced in volcanic arcs, and in mountain buildings where it emplaces as large batholiths in mountain roots. Granodiorite is the plutonic equivalent of dacite. 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.Granodiorite is a coarse-grained intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. According to the QAPF diagram, granodiorite has a greater than 20% quartz by volume, and between 65% and 90% of the feldspar is plagioclase.GRANDIORITE. / Locality: / Harcourt, Victoria / Other label: Geological survey / R S / Loc Harcourt quarries [?] Alexander / 1/4 Sheet. | 4 | Granite /granodiorite, granite, burke museum, harcourt, coarse-grained, igneous, plagioclase feldspar, orthoclase feldspar, quartz, mount alexander, the dja dja wurrung people, the traditional owners, central highlands of victoria, gold rush

This specimen was recovered from Ceres West of Geelong, Victoria. Greenstone is the name for any metamorphosed basic igneous rock (in the case of this specimen, Gabbro) that gains its greenish colour to the presence of the minerals chlorite, actinolite, or epidote, hence the term 'green' and 'stone'. Greenstone is often formed through metamorphsis along a convergent plate boundary. In the rock cycle (the series of processes that creates the various types of rocks) there are identified three different types of rocks, which are the sedimentary, the igneous and the metamorphic. Metamorphic rocks started out as sedimentary, igneous or earlier metamorphic rocks but changed from their original condition under the effect of high heat, high pressure or hot, mineral-rich fluid. However, if pressure or heat is too high, then the rock will melt, resulting in the formation of an igneous rock. The name used to describe these types of rocks reflects this specific inherent trait of change, since the word “metamorphic” derives from the Greek word “metamorphosis”, meaning “change of form or structure”. Metamorphic rocks form in the Earth`s crust but can be also found on the surface, due to elevation of the Earth`s surface. They are divided into two categories: the foliated metamorphic and the non-foliated metamorphic rocks. Gabbro is a highly useful mineral that is often polished to create cemetery markers and kitchen benches. It is notable for its qualities of durability, being able to withstand extreme elements and wear. Whilst not rare, Gabbro is of great utility and has been highly desirable for its qualities. 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.Greenstone is a solid hand-sized metamorphic mineral of a green colour. Greenstone is the name for any metamorphosed basic igneous rock (in the case of this specimen, Gabbro) that gains its greenish colour to the presence of the minerals chlorite, actinolite, or epidote, hence the term 'green' and 'stone'. Gabbro is a medium to coarse grained rocks that consist primarily of plagioclase feldspar and pyroxene. Greenstone is often formed through metamorphsis along a convergent plate boundary. Gabbro forms due to cooling and crystallization of magma underneath Earth's surface. Greenstone/Gabbro/from Ceres west/of Geelong. Has old Geological Survey label/and probably collected by/Richard Daintree in 1861/C.Willam 15/4/21/ Other label: 62 /greenstone, metamorphosed, igneous rock, gabbro, chlorite, actinolite, epidote, metamorphsis, rock cycle, various types of rocks, sedimentary, high heat, high pressure, mineral-rich fluid, metamorphosis, foliated metamorphic, non-foliated metamorphic, convergent plate boundary, greenish colour, minerals

Feldspathic arenites are sandstones that contain less than 90% quartz, and more feldspar than unstable lithic fragments, and minor accessory minerals.Feldspathic sandstones are commonly immature or sub-mature.These sandstones occur in association with cratonic or stable shelf settings. Feldspathic sandstones are derived from granitic-type, primary crystalline, rocks. If the sandstone is dominantly plagioclase, then it is igneous in origin Sandstone features prominently in public buildings throughout Victoria. Most of the sandstone used as dimension stone in the State came from three sources: the Heatherlie quarry in the Grampians (Silurian), the Bacchus Marsh area (Permian), and the Barrabool Hills near Geelong (Cretaceous).Sandstone features prominently in public buildings throughout Victoria, making this specimen special as it shows the materials used by Victorian building companies. Sandstone can also be crushed, crushed stone is used in the construction of roadways and road structures such as bridges, and in buildings, both commercial and residential. 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 feldspar-rich sandstone, a sandstone intermediate in composition between an arkosic sandstone and a quartz sandstone, containing 10% to 25% feldspar and less than 20% matrix material of clay, sericite, and chlorite. Feldspathic arenite containing less than 90 percent of the composition of quartz. Feldspar is the main composition. Feldspathic arenite may contain fragments of unstable rock, and a little amount of other minerals such as mica and heavy minerals. Some feldspathic arenite have pink or red color because of the presence of potassium feldspar or iron oxide. There are also colored light gray to white. These sandstones are usually medium to coarse grained and can contain a high percentage of granules with angular until subangular roundness. The content of the matrix can appear as the rest up to more than 15 percent, and sorting of grains can present as moderate to poorly sorted. Feldspathic sandstones are generally immature in textural maturity. Feldspathic arenite can not be judged from the structure of the sediment. Bedding can emerge from the laminate parallel to the crossbed. Fossils may appear in the layer deposited on the sea. Feldspathic arenites usually appear on the craton or the continental shelf, which can be associated with conglomerate, quartz lithic arenite, carbonate rock, or evaporites. This sandstone may also appear on the succession of sedimentary basins deposited on an unstable or deep sea, and moving arc setting. According to Pettijohn (1963) Arkose make up about 15 percent of all sandstones. Some Arkose formed in situ when the granite and related rocks disintegrate and generate granular sediments. Most of the material feldspathic sandstones derived from primary crystalline granitic rocks, such as granite or metasomatic rocks containing abundant potassium feldspar. Mineral contained in sandstones is mostly a form of plagioclase feldspar derived from quartz diorite or volcanic rock. Feldspar contained on this sandstone comes from arid to cool climates when the chemical weathering process is reduced.sandstone, natural stone, feldspathic sandstone, burke museum, geology, geological, geological specimen