1.1" Quartz, Calcite and Pyrite Association - China

This is a beautiful specimen that displays an association of calcite and dolomite crystals that cover a pyrite encrusted quartz crystal. This mineral association was collected from the Hunan Province of China and comes on a piece of mineral tack within an acrylic perky display case.

Silicon Dioxide, also known as SiO2 or Quartz, is the second most abundant mineral in the Earth's crust. Quartz crystals generally grow in silica-rich, hot watery solutions called hydrothermal environments, at temperatures between 100°C and 450°C, and usually under very high pressure. Quartz veins are formed when open fissures are filled with hot water during the closing stages of mountains forming, and can be hundreds of millions of years old.

Calcite, CaCO3, is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite. Calcite crystals are trigonal-rhombohedral, though actual calcite rhombohedra are rare as natural crystals. However, they show a remarkable variety of habits including acute to obtuse rhombohedra, tabular forms, and prisms. Calcite exhibits several twinning types adding to the variety of observed forms. It may occur as fibrous, granular, lamellar, or compact. Cleavage is usually in three directions parallel to the rhombohedron form.

The mineral pyrite or iron pyrite is commonly referred to as Fool's Gold because its metallic luster and pale brass-yellow hue give it a superficial resemblance to gold. In the old mining days, pyrite was sometimes mistaken for gold. Pyrite is the most common of the sulfide minerals with the chemical formula FeS2. Pyrite crystals occur in many shapes and habits, including cubes of all sizes, penetration twin cubes, pyritohedral clusters and as small druzy crystals that can exhibit a beautiful glistening effect.

Dolomite is an anhydrous carbonate mineral composed of calcium magnesium carbonate—CaMg(CO3)2.

The mineral dolomite crystallizes in the trigonal-rhombohedral system. It forms white, tan, gray, or pink crystals. Dolomite is a double carbonate, having an alternating structural arrangement of calcium and magnesium ions. It does not rapidly dissolve in dilute hydrochloric acid as calcite does. Crystal twinning is common.

The mineral dolomite was first described by Carl Linnaeus in 1768 and In 1791, it was described as a rock by the French naturalist and geologist Déodat Gratet de Dolomieu who first recognized the material in buildings of the old city of Rome, and later as samples collected in the mountains known as the Dolomite Alps of northern Italy.
SOLD
DETAILS
SPECIES
Quartz, Dolomite, Pyrite & Calcite
LOCATION
China
SIZE
1.1 x 1.08"
CATEGORY
ITEM
#161626