What is the characteristics of pegmatite?

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 does a pegmatite rock look like?

They are extreme because they contain exceptionally large crystals and they sometimes contain minerals that are rarely found in other types of rocks. To be called a “pegmatite,” a rock should be composed almost entirely of crystals that are at least one centimeter in diameter.

How do you distinguish between a granite and pegmatite?

Pegmatite is chemically identical to granite, but has a much coarser crystal structure. Common colors are gray, white, and pink. Pegmatite is quarried for decorative stone and as a source of beryllium, columbium and tantalum when these are present.

What defines a pegmatite?

pegmatite, almost any wholly crystalline igneous rock that is at least in part very coarse grained, the major constituents of which include minerals typically found in ordinary igneous rocks and in which extreme textural variations, especially in grain size, are characteristic.

What texture is pegmatite?

PEGMATITE is a common plutonic rock, of variable texture and coarseness, that is composed of interlocking crystals of widely different sizes. The most spectacular pegmatites contain abnormally large crystals mixed with medium sized and smaller crystals. Crystals up to many meters long have been reported.

What color is pegmatite?

The color of the pegmatite is clear, between white and pink. There are also some variety of gray and cream colors. It has large crystals and penetration twins.

What color is a pegmatite rock?

The color of the pegmatite is clear, between white and pink. There are also some variety of gray and cream colors. It has large crystals and penetration twins. When rock structures are analyzed, each one has something different.

What is the color of pegmatite rock?

Pegmatite in which the main ingredients are biotite mica (black), microcline (pink), oligoclase (white), and quartz (gray). The rock has a monzogranitic composition.

What is the size of pegmatite?

A pegmatite is an igneous rock, formed by slow crystallization at high temperature and pressure at depth, and exhibiting large interlocking crystals usually greater in size than 25 mm (0.98 in).

How big are crystals in pegmatite?

Why are pegmatites called Nature’s jewelry box?

Minas Gerais is rich in granite geologic formations known as pegmatites. These pegmatites are sometimes called “nature’s jewel box” because of the vast array of gemstones that they may contain. Huge quantities are mined from the basaltic lava flows to supply the gem markets around the world.

Are diamonds found in Georgia?

DIAMOND: The occurrence of diamonds in Georgia dates back to the days of early placer gold mines. Dr. M. F. Stephenson, Director of the Dahlonega Mint, discovered the first Georgia diamond in 1843, while panning for gold at Williams Ferry.