Physics

Staurolite Definition Staurolite is a brownish to black orthorhombic mineral, often having crossed intergrown crystals and found in mica schists and gneisses. Its chemical formula:…

Topaz Definition Topaz is a colorless, blue, yellow, brown, or pink orthorhombic mineral valued as a gem. Topaz occurs as transparent or translucent prisms in…

Sillimanite Definition Sillimanite is a usually white, pale-green or brown orthorhombic mineral occurring as long, slender, fibrous crystals in metamorphic rocks. It is a polymorph…

Kyanite Definition Kyanite is a bluish-green to colorless triclinic mineral. Its chemical formula: Al2SiO5. It occurs as long, thin, blade-shaped crystals in metamorphic rocks. It…

Andalusite Definition Andalusite is a hard, grayish white to pinkish brown orthorhombic mineral. It occurs as nearly square prisms, often with cross-shaped cross sections, in…

Thorite Definition Thorite is a yellow, brownish, or black radioactive mineral consisting of tetragonal thorium silicate. It occurs in coarse granite and is a source…

Zircon Definition Zircon is a brown, reddish to bluish, gray, green, or colorless tetragonal mineral that occurs in igneous, metamorphic, and sedimentary rocks, and especially…

Grossular Definition Grossular is the calcium aluminum garnet and forms in contact or regional metamorphic environments as does andradite the calcium iron garnet. It is…

Almandine Definition Almandine is a deep violet-red garnet that consists of iron aluminium silicate and is used as a gemstone. It is known as a…

Pyrope Definition Pyrope is a deep yellowish-red garnet that consists of magnesium aluminium silicate and is used as a gemstone. It is a member of…

Forsterite Definition Forsterite is any of a group of magnesium iron silicates, (Mg,Fe)2SiO4, occurring in olive-green to gray-green masses as an important constituent of basic…

Phenakite Definition Phenakite is a colourless or white glassy mineral consisting of beryllium silicate in hexagonal crystalline form: occurs in veins in granite with formula:…