Brachinite Explained

Brachinites are a group of meteorites that are classified either as primitive achondrites or as asteroidal achondrites. Like all primitive achondrites, they have similarities with chondrites and achondrites. Brachinites contain 74 to 98% (volume) olivine.

Naming and history

Brachinites are named after the Brachina meteorite, the type specimen of this group, which in turn is named after Brachina, South Australia.[1]

Description

Brachinites consist almost entirely of olivine (74 to 98% by volume). Other minerals include plagioclase (6.7 to 12.9%), iron sulfides (1.8 to 4.0%), clinopyroxene (1.5 to 8.2%) and orthopyroxene (0 to 2.4%). Trace minerals include phosphates and meteoritic iron. The only deviation from chondrites is the very high olivine/orthopyroxene ratio.[2]

Specimens

As of 2022, there were 56 meteorites classified as brachinites.[3] A notable example is the type specimen, the Brachina meteorite.

See also

Notes and References

  1. Web site: Brachina. Meteoritical Society. 21 November 2022.
  2. Nehru. C. E.. M. Prinz . M. K. Weisberg . M. Ebihara . R. N. Clayton . T. K. Mayeda . Brachinites: A New Primitive Achondrite Group. Meteoritics. 1992. 27. 3. 267.
  3. Web site: Meteoritical Bulletin Database. Meteoritical Society. 21 November 2022.