Definitions

humite group

Humite

Humite is an orthorhombic mineral of a transparent vitreous brown to orange color. It is found in the volcanically ejected masses of Vesuvius. It is a nesosilicate of iron and magnesium which also contains fluorine and hydroxide. The formula is: (Mg,Fe)7(SiO4)3(F,OH)2.

It was first described in 1813 and named for Abraham Hume (1749-1838).

Humite is also used as the name of a group of closely related minerals -- humite, clinohumite, chondrodite, and norbergite. These minerals are similar in structure and in chemistry. Deer et al. (1997) note that a general formula for the humite-group minerals can be simply expressed as nM2SiO4 . M(OH,F)2 , where M is Mg, Fe, Ti etc. and n = 1 (norbergite), 2 (chondrodite), 3 (humite), and 4 (clinohumite). Deer et al. (1997) also note that although the formula above correctly describes the chemistries of these minerals, structural formulas are more complex.

See also

References

  • Deer, W. A., Howie, R. A., and Zussman, J., 1997, Rock-forming minerals: Volume 1A, Second Edition, Orthosilicates. The Geological Society, Bath, UK. ISBN 1-897799-8-8

External links

Search another word or see humite groupon Dictionary | Thesaurus |Spanish
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature