English | Български
Where am I? > Home > Classification > Sphalerite

Quick navigation selector


Class: Sulphides & sulphosalts
Group: Sphalerite

Varieties | Names:

Formed under a wide range of low- to high-temperature hydrothermal conditions; in coal, limestone, and other sedimentary deposits (Anthony et al., 2001—2005). There are faceted specimens from Spain over 350 carats.

Original description: unknown.

Type locality: unknown.

Type material: unknown.

Etymology: from the Greek word σφαλεροζ (sphaleros) meaning treacherous; the mineral sometimes being mistaken for galena, but yielding no lead.

Distribution: оnly a few localities for the finest crystallised examples can be given. Canada: Yukon Territory, Watson Lake; Czech Republic: at Horní Slavkov (Schlaggenwald); England: Cumbria, from Alston Moor; Germany: from Freiberg, Saxony, and Neudorf, Harz Mountains; Mexico: from Santa Eulalia and Naica, Chihuahua, and Cananea, Sonora; Peru: Huaron, Casapalca, and Huancavelica; Romania: Rodna; Russia: Primorsky Krai, Dalnegorsk; Spain: Cantabria [Santander] Province, Picos de Europa Mts, Aliva mine; Switzerland: Valais, Binntal, Lengenbach quarry; USA: Kansas, Cherokee Co., near Baxter Springs; Missouri, Jasper Co., Joplin; Oklahoma, Ottawa Co., Picher; Tennessee, Smith Co., near Carthage, Elmwood mine; Colorado, Eagle Co., Gilman district, Eagle mine (Anthony et al., 2001—2005). In Bulgaria from Smolyan District, Madan region.



Essential elements: sulphur (S), zinc (Zn).

Crystal data

Crystallography: isometric — hextetrahedral. Crystal habit: crystals tetrahedral, dodecahedral, typically complex and distorted, curved and conical faces common, to 30 cm; also fibrous, botryoidal, stalactitic, cleavable, coarse to fine granular, massive. Twinning: twin axis [111], twin plane {111}, simple contact twins or complex lamellar forms (Anthony et al., 2001—2005).

Physical properties

Cleavage: perfect on {011} (Anthony et al., 2001—2005). Fracture: conchoidal (Anthony et al., 2001—2005). Tenacity: brittle (Anthony et al., 2001—2005). Hardness: 3.5—4 (Arem, 1987: 176). Density: 3.95—4.1 g/cm3 (Lazzarelli, 2012). Luminescence: fluorescent, yellow-orange under SW UV and LW UV; triboluminescent.

Optical properties

Colour: highly variable, ranging from colourless to dark brown, grey, black; commonly brown, yellow, red, green (Anthony et al., 2001—2005). Diaphaneity: transparent to translucent, opaque when iron-rich (Anthony et al., 2001—2005). Lustre: resinous to adamantine (Anthony et al., 2001—2005). Refractive index: 2.368—2.371 — isotropic (Lazzarelli, 2012). Dispersion: very strong; 0.156 (Arem, 1987: 176); nearly four times that of diamond. Pleochroism: none.

Material from ‘Repository’

2 specimens: 0198 — 0.15 ct, Spain; 0391 — 1.73 ct, Spain.

Gallery view