What is "mica"

Mica \Mi"ca\, n. [L. mica crumb, grain, particle; cf. F. mica.] (Min.) The name of a group of minerals characterized by highly perfect cleavage, so that they readily separate into very thin leaves, more or less elastic. They differ widely in composition, and vary in color from pale brown or yellow to green or black. The transparent forms are used in lanterns, the doors of stoves, etc., being popularly called isinglass. Formerly called also cat-silver, and glimmer.

Note: The important species of the mica group are: muscovite, common or potash mica, pale brown or green, often silvery, including damourite (also called hydromica and muscovy glass); biotite, iron-magnesia mica, dark brown, green, or black; lepidomelane, iron, mica, black; phlogopite, magnesia mica, colorless, yellow, brown; lepidolite, lithia mica, rose-red, lilac. [1913 Webster] Mica (usually muscovite, also biotite) is an essential constituent of granite, gneiss, and mica slate; biotite is common in many eruptive rocks; phlogopite in crystalline limestone and serpentine.

Mica diorite (Min.), an eruptive rock allied to diorite but containing mica (biotite) instead of hornblende.

Mica powder, a kind of dynamite containing fine scales of mica.

Mica schist, Mica slate (Geol.), a schistose rock, consisting of mica and quartz with, usually, some feldspar.

1706, from specialized use of Latin mica "crumb, bit, morsel, grain," originally *smika (form probably influenced by Latin micare "to flash, glitter"), from PIE *smik- "small" (cognates: Greek smikros, Attic mikros "small;" Old High German smahi "littleness"). Related: Micaceous "containing mica."

n. Any of a group of hydrous aluminosilicate minerals characterized by highly perfect cleavage, so that they readily separate into very thin leaves, more or less elastic.

n. any of various minerals consisting of hydrous silicates of aluminum or potassium etc. that crystallize in forms that allow perfect cleavage into very thin leaves; used as dielectrics because of their resistance to electricity [syn: isinglass]

The mica group of sheet silicate ( phyllosilicate) minerals includes several closely related materials having nearly perfect basal cleavage. All are monoclinic, with a tendency towards pseudohexagonal crystals, and are similar in chemical composition. The nearly perfect cleavage, which is the most prominent characteristic of mica, is explained by the hexagonal sheet-like arrangement of its atoms.

The word mica is derived from the Latin word , meaning a crumb, and probably influenced by , to glitter.

The MBDA MICA (Missile d’interception, de combat et d’autodéfense, “interception, combat and self-defence missile”) is an anti-air multi-target, all weather, fire-and-forget short and medium-range missile system. It is intended for use both by air platforms as individual missiles as well as ground units and ships, which can be equipped with the rapid fire MICA Vertical Launch System. It is fitted with a thrust vector control (TVC) system. It was developed from 1982 onward by Matra. The first trials occurred in 1991, and the missile was commissioned in 1996 to equip the Rafale and Mirage 2000. It is a replacement for both the Super 530, in the interception role, and the Magic II, in the dogfighting role.

On 11 June 2007, a MICA launched from a Rafale successfully demonstrated its over-the-shoulder capability by destroying a target behind the launch aircraft. The target was designated by another aircraft and coordinates were transmitted by Link 16.

Mica and similar may refer to:

• Mica, a group of sheet silicate minerals

MICA is an academic institution for Strategic Marketing and Communication skills in India. Established in 1991, it is located on the outskirts of the western Indian city of Ahmedabad. Recently, on March 29, 2014, amidst the nineteenth convocation, MICA launched its new logo while still retaining its vision to create leadership in Strategic Marketing & Communication, as also its tagline- ‘The school of Ideas’. MICA has now dropped its acronym and will now be known as only 'MICA'.