Research Results For 'Augite'

AUGITE

Augite is an important rock forming mineral of the pyroxene group. Chiefly found in dark coloured igneous rocks, especially those whose magmas were rich in iron, calcium and magnesium. Seldom found in rocks that contain much quartz. A common member of the pyroxene group. Told from the amphibole group by cleavage. It has the formulae (Ca,Na) (Mg,Fe,Al,Ti)(Si,Al)2O6 and a relative hardness of 6. When crystallized it assumes the form of short, slightly rhombic prisms, with their lateral edges replaced, and terminated at one or both extremities by numerous planes. A transparent green variety found at Zillerthal, in the Tyrol, is used in jewelry.
Research Augite

BASALT

Basalt is an igneous rock, consisting of augite and triclinic feldspar, with grains of magnetic or titanic iron, and also bottle-green particles of olivine frequently disseminated. It is usually of a greenish black colour, or of some dull brown shade, or black. It constitutes immense beds in some regions, and also occurs in veins or dikes cutting through other rocks. It has often a prismatic structure as at the Giant's Causeway, in Ireland, where the columns are as regular as if the work of art. It is a very tough and heavy rock, and is one of the best materials for macadamising roads.
Research Basalt

DIABASE

Diabase is a dark, intrusive, basic igneous rock made up of plagioclase feldspar crystals, surrounded by smaller grains of pyroxenes, such as augite and up to ten percent quartz. Diabase is formed from magna that has cooled just below the Earth's surface, and is sometimes found as intrusions in older rock. A common place to find diabase is in the neck of old volcanoes, where it has formed a plug.
Research Diabase

ECLOGITE

Eclogite is a rock which consists of pale-green augite, pale-green hornblende, pink garnet with sometimes also quartz, feldspar, cyanite, bronzite, iron ores and rutile. Such rocks occur in regions of xrystalline schists, as the Alps, and are believed to be of intrusive origin in some cases.
Research Eclogite

FAUJASITE

Faujasite, named after the French geologist Faujas de Saint-Fond is a silicate occurring in square octahedrons together with black augite in the mandelstein of the Kaiserstuhl in Baden.
Research Faujasite

GABBROS

Gabbros are basic rocks solidified under great pressure at considerable depths in the earth's crust. They are coarse-grained and consist of plagioclase feldspar with augite. Sometimes the term is used to include similar rocks composed of the same feldspar with other minerals, and according to the minerals contained they are known as norites, troctolites, eucrites, etc.
Research Gabbros

GREYSTONE

Greystone is a greyish or greenish compact rock, composed of feldspar and augite, and allied to basalt.
Research Greystone

PHONOLITE

Phonolite or clinkstone is a volcanic rock, consisting essentially of nepheline and sanidine feldspar. It usually also contains some form of augite, hornblende or biotite.
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PICRITE

Picrite is a crystalline igneous rock which consists essentially of olivine and augite, but usually also contains iron oxides, a little feldspar, biotite, hornblende and apatite.
Research Picrite

SYENITE

Syenite is a plutonic igneous rock consisting essentially of alkali-feldspar and one or more ferro-magnesian minerals, such as augite, hornblende, or mica.
Syenite is often mistake for granite because of its colour, but has a lower silica content.
Research Syenite

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