What are granitic pegmatites?
Granitic pegmatite. Pegmatites are extreme igneous rocks that form during the final stage of a magma’s crystallization. They are extreme because they contain exceptionally large crystals and they sometimes contain minerals that are rarely found in other types of rocks.
What minerals are in granite pegmatite?
The word pegmatite derives from Homeric Greek, πήγνυμι (pegnymi), which means “to bind together”, in reference to the intertwined crystals of quartz and feldspar in the texture known as graphic granite. Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic composition as granite.
What is the composition of pegmatite?
The pegmatite contains 33.6 percent albite, 30.4 percent quartz, 21.0 percent perthite, 14.0 percent muscovite, and 1.0 percent accessory minerals. Its bulk chemical composition is 74.2 per- cent SiO2, 15.0 percent A12Oa, 4.6 percent NarO, 4.2 percent KrO, 0.6 percent HzO, and 1.4 percent other constituents.
What is granite used for?
Granite has been in use for thousands of years as dimension stone, construction material, decorative, and architectural stone. The natural stone has also been used in bridges, paving and in multiple exterior projects. As an elegant and prestigious material, granite is ideal for a range of interior projects.
What minerals are obtained from pegmatites and what do we use them for?
Pegmatite is used for rare mineral mining. These minerals can be commercial sources of: beryllium, bismuth, boron, cesium, lithium, molybdenum, niobium, tantalum, titanium, tungsten, and many other elements. Pegmatite is frequently mined for industrial minerals. Large sheets of mica are mined from pegmatite.
Which of the following is a characteristic of pegmatites?
Pegmatites contain exceptionally large crystals and they contain rarely minerals than other types of rocks. They have interlocking crystals usually larger than 2.5 cm in size. Generally most Pegmatites are found in sheets of rock that are dikes and veins Also near large masses of igneous rocks called batholiths.
What is the meaning of Phaneritic?
[ făn′ə-rĭt′ĭk ] Of or relating to an igneous rock in which the crystals are so coarse that individual minerals can be distinguished with the naked eye. Phaneritic rocks are intrusive rocks that cooled slowly enough to allow significant crystal growth. Compare aphanitic.
What is composition of granite?
(2) Natural Granite. Granite is the typical type of plutonic rocks, it consists of feldspar, quartz, a few dark—colored mineral, sand, mica. The main chemical propositions of the granite are SiO2 (65% ~ 70%), a little of Al2O3,CaO,MgO and Fe2O3, thus the granite is acid rock.
