How do I identify Spurrite?

Spurrite can be identified by its hardness of 5 on the Mohs scale, Colourless color. Look for these key characteristics when examining specimens.

What color is Spurrite?

Spurrite typically appears in Colourless, grey-white, lilac-grey. Color can vary depending on impurities and formation conditions.

How hard is Spurrite?

Spurrite has a hardness of 5 on the Mohs scale. This gives it moderate hardness.

Spurrite

A variety of Minerals

What is Spurrite?

Spurrite is a white, yellow or light blue mineral with monoclinic crystals. Its chemical formula is Ca5(SiO4)2CO3. Spurrite is generally formed in contact metamorphism zones as mafic magmas are intruded into carbonate rocks. Spurrite's space group is P 2/a. It is biaxial with a birefringence of 0.0390–0.0400, giving second order red interference colors when viewed under crossed polarizers in a petrographic microscope. The calcium is in six-fold coordination with the oxygen, the silicon is in a four-fold coordination with the oxygen and the carbon is in two-fold coordination. One unique characteristic of spurrite is that it actually abides by two twin laws. Polysynthetic twinning can occur along its (001) and another type of twinning can occur parallel to its optical axes.

Spurrite Market Value Calculator

Estimate the market value of Spurrite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.

Spurrite Localities Map

See where Spurrite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.

Map preview

North ZoneCentral RidgeSouth Basin

Key Characteristics

Formation of Spurrite

Spurrite was first described in 1908 for an occurrence in the Terneras Mine, Velardeña District, Durango, Mexico. It was named for American economic geologist Josiah Edward Spurr (1870–1950). In addition to its type locality, spurrite has been reported from Riverside County, California; Luna County, New Mexico; and from the Little Belt Mountains, Lewis and Clark County, Montana. It is also found in Ireland, Scotland, New Zealand, Turkey, Israel, Japan and Siberia.