| Satin spar | |
|---|---|
 | |
| General | |
| Category | Mineral |
Satin spar (German: atlasspat, atlasspath, atlasstein), less commonly atlas spar — is a trivial, partly obsolete name for fibrous varieties of two minerals, gypsum and calcite,[1]: 40 possessing a characteristic silky (satin) luster. Despite their very low hardness (2 or 3 on the Mohs scale), both atlas (satin) spars (especially selenite) are widely used as ornamental stones.
It should be understood that both of the listed minerals, despite their name of “spars”, do not strictly belong to the number of the most well-known under this name feldspars — both from the point of view of chemical composition and from the standpoint of classical mineralogy.
- ^ Krivovichev V. G. Mineralogical glossary. Scientific editor A. G. Bulakh. — St.Petersburg: St.Petersburg Univ. Publ. House. 2009. — 556 p. — ISBN 978-5-288-04863-0. (in Russian)