Minerals

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A mineral is a naturally occurring chemical compound usually of crystalline form and not produced by life processes. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids. The study of minerals is called mineralogy. To meet the definition of “mineral” used by most geologists, a substance must meet five requirements:

Orpiment

An arsenic sulfide, orpiment is a soft yellow or orange mineral. Widely distributed, it is typically powdery or massive, but it is also found as cleavable, columnar, or foliated masses. Distinct crystals are uncommon, but when found they are short prisms.

Realgar 

An important ore of arsenic, realgar is bright red or orange in color. Crystals are not often found, but when they occur they are short, prismatic, and striated. Realgar mostly occurs as coarse to fine granular masses and as encrustations.

Cinnabar

A mercury sulfide, cinnabar takes its name from the Persian zinjirfrah and Arabic zinjafr, which mean “dragon’s blood.” It is bright scarlet to deep grayish red in color. It is the major source of mercury.

Chalcopyrite

Chalcopyrite is a copper include sulfide mineral .It has to formula CuFeS2.It is usually seed brassy to golden yellow color .Also copper is most important ore mineral thousands of years. Hardness of 3.5 – 4 on the Mohs scale and diagnostic properties streak is black green

Galena

Galena is most abundant and widely found sulfide mineral and other name is lead glance .It is most important minerals of lead and silver.Crystal system is cubic ,isometric system and xpl features not observed. It is often associated with the minerals sphalerite, calcite and fluorite.

Spinel

Spinel is the name of both an individual mineral and of a group of metal-oxide minerals that share the same crystal structure. Minerals in this group include gahnite, franklinite, and chromite. Spinel is found as glassy, hard octahedra, or as grains or masses.

Goethite

Named after the German mineralogist Johann Wolfgang von Goethe in 1806, goethite is a common mineral. It can be brownish yellow, reddish brown, or dark brown in color, depending on the size of the crystal in the specimen—small crystals appear lighter, and larger ones darker.

Magnetite

Magnetite is rock mineral and one of the most importan iron ore minerals with chemical formula is iron(II,III) oxide, Fe2+Fe3+2O4 .It also Magnetite is as the name magnetic minerals to attracted to a magnet. It is the most magnetic natural occuring minerals in the World. Small grains of magnetite occur in almost all igneous and metamorphic rocks.

Hematite

Dense and hard, hematite is the most important ore of iron (p.39) because of its high iron content and its abundance. The mineral occurs in various habits: steel-gray crystals and coarse-grained varieties with a brilliant metallic luster are known as specular hematite;

Malachite

Possibly the earliest ore of copper, malachite is believed to have been mined in the Sinai and eastern deserts of ancient Egypt from as early as 3000 BCE. Single crystals are uncommon; when found, they are short to long prisms.

Dolomite

An important rock-forming mineral, dolomite is named after the French mineralogist Déodat Gratet de Dolomieu. It is a colorless to white, pale brown, grayish, reddish, or pink mineral. Its crystals are commonly rhombohedral or tabular, often have curved faces, and sometimes cluster in saddle-shaped aggregates.

Calcite

Calcite is a rock-forming mineral with a chemical formula of CaCO3. It is extremely common and found throughout the world in sedimentary, metamorphic, and igneous rocks. Some geologists consider it to be a "ubiquitous mineral" - one that is found everywhere.