Brachina meteorite

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The Brachina meteorite is the type specimen of brachinites, a small group of asteroidal achondrites. Named after Brachina in South Australia, two fragments weighing about 200 g were found on 26 May 1974 by B. M. Eves at 31°18′S 138°23′E.

Its mineral makeup is mostly olivine (about 80%), with plagioclase (10%), clinopyroxene (5.5%), iron-sulfide (3%), chromite (0.5%), chlorapatite (0.5%), pentlandite (0.3%), and traces of meteoric iron. Melt inclusions are glass with orthopyroxene and anorthoclase.

The chemical and mineral pattern is similar to the Chassigny meteorite, but trace elements are fundamentally different. It was first classified as a chassignite in 1978, but 1983 trace-element studies showed it was distinct, leading to it being named the type specimen of a new class, brachinites, a classification used ever since.