Historical information
Basalt is a common igneous rock that composes most of the Earth's surface and can be found on the Moon and other rocky planets of the Solar System. It is generally composed minerals such as calcic plagioclase, clinopyroxene and iron ore which form grains that are indistinguishable to the naked eye. It can be dark grey or black in colouring and sometimes may contain holes left by gas bubbles. Most of the Earth's basalt was produced in environments such as oceanic divergent boundaries, oceanic hotspots, and mantle plumes and hotspots beneath continents.
Basalt is commonly used in construction where it is crushed and used for multiple purposes such as concrete aggregate, road base, or railroad ballast. Thin slabs of basalt can also be cut and used for floor tiles, stone monuments, and building veneer.
This particular specimen was excavated from Talbot in Victoria, which was a small gold mining town established in 1852. As basalt is a common rock, it is not specific to Talbot. However, this specimen can be assumed to be of the Cainozoic age due to previous geomorphic surveys of the area. This particular type of Basalt was used mainly for roads due to the durability of the rock.
Significance
Basalt holds significance due to the continued use of the rock from historic until present times. The rock has been utilised for many types of construction and is still used for the same purposes today. Basalt also has significance to the Earth and other rocky planets of the Solar System as it makes up most of the planet's surface.
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.
Physical description
A smaller than hand sized rock specimen which is dark grey in colour with small holes and white deposits across its surface.
Inscriptions & markings
Geological survey / [illegible] /