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Mineral symbols (text abbreviations) are used to abbreviate mineral groups, subgroups, and species, just as lettered symbols are used for the chemical elements.. The first set of commonly used mineral symbols was published in 1983 and covered the common rock-forming minerals using 192 two- or three-lettered symbols. [1]
Basalt (UK: / ˈ b æ s ɒ l t,-ɔː l t,-əl t /; [1] [2] US: / b ə ˈ s ɔː l t, ˈ b eɪ s ɔː l t /) [3] is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon.
Beach pebble of variolitic pillow lava (varolite) from the Olympic Peninsula, Washington stateVariolites are mafic, igneous, and typically volcanic rocks, e.g. tholeiite, basalt or komatiite, that contain centimeter-scale spherical or globular structures, called varioles, in a fine-grained matrix.
The calc-alkaline magma series is one of two main subdivisions of the subalkaline magma series, the other subalkaline magma series being the tholeiitic series. A magma series is a series of compositions that describes the evolution of a mafic magma, which is high in magnesium and iron and produces basalt or gabbro, as it fractionally crystallizes to become a felsic magma, which is low in ...
Sima often takes the form of basalt when on the surface. In geology, sima (/ ˈ s aɪ m ə /) is an antiquated [1] blended term for the lower layer of Earth's crust. This layer is made of rocks rich in magnesium silicate minerals. Typically, when the sima comes to the surface, it is basalt, so sometimes this layer is called the 'ocean layer' of ...
The quarry landscape of the Northern Faiyum Desert comprise both the Umm es-Sawan and Widan el-Faras basalt quarries, both heavily exploited for hardstone during the Old Kingdom pyramid age due to their proximity to the Nile Valley. [1] The quarry was active between the Old Kingdom and Late Period. [1]
The tablet measures 24.1 by 20.1 cm and seems to be made from locally sourced vesicular basalt. [5] [1] The carving was made with a conical drill and then smoothed. [2]
Hawaiite is an olivine basalt with a composition between alkali basalt and mugearite. [1] It was first used as a name for some lavas found on the island of Hawaii.. It occurs during the later stages of volcanic activity on oceanic islands such as Hawaii, [2] which happens to be when the alkali metals are most present.