Calcite Gemstones

Calcite, a versatile and abundant gemstone, enchants with its remarkable variety of colors, ranging from clear and white to vibrant hues of orange, blue, and green. As one of the most common minerals in the Earth’s crust, this carbonate gem is celebrated for its stunning crystal formations and optical properties, including double refraction, which creates a mesmerizing visual effect. Found in diverse locations worldwide, from Mexico to Iceland, calcite’s accessibility, beauty, and unique characteristics make it a favorite among collectors and crystal enthusiasts. Discover our collection of calcite gemstones for sale.

Different Calcite Colors

Calcite is a mineral that belongs to the carbonate group and is composed of calcium carbonate. It is commonly found in sedimentary rocks and has a wide range of applications in various industries. Calcite is known for its distinct crystal structure and can exhibit a variety of colors, including white, gray, yellow, and green. With a hardness of only 3 on the Mohs scale, it can only be used in jewelry that won't be subjected to knocks or scratches, such as earrings and pendants. Its hardness is similar to that of gems like amber, coral and chrysocolla. However, calcite is not only soft but, like most carbonates, it is senstive to acid, which can dissolve it.

Though calcite is not an especially durable material, it does take an excellent polish. Many historical artifacts identified as alabaster are in fact made from calcite.

Pure calcium carbonate is colorless, but calcite is often colored by various impurities, including iron, magnesium, manganese, zinc or cobalt. Thus calcite can be found in a range of colors including white, gray, yellow, green, red and blue.

Calcite is a common constituent of sedimentary rocks, limestone in particular, much of which is formed from the shells of dead marine organisms. Approximately 10% of all sedimentary rock is limestone.

Calcite is the primary mineral in metamorphic marble. It also occurs as a vein mineral in deposits from hot springs, and it occurs in caverns as stalactites and stalagmites.

Calcite is the primary ore of calcium. Calcite is indispensable in the construction industry, forming the base of cement. Many important chemicals are created from calcite. It is also crucial in the manufacture of fertilizer, metal, glass, rubber and paint. The transparent Iceland Spar variety, in which the double refraction is clearly apparent, was used as prisms for polarizing microscopes and other optical devices. Calcite forms rocks that are used for ornamental purposes, such as various kinds of marble. Calcite is also the main component of chalk.

Calcite from Namibia