| Angrite | |
|---|---|
| — Group — | |
A slice of "NWA 2999". Note the similarity to a terrestrial basalt. | |
| Compositional type | Stony meteorite |
| Type | Achondrite |
| Subgroups | Quenched Plutonic |
| Parent body | Possibly 289 Nenetta, 3819 Robinson or Mercury |
| Total known specimens | 30+ |
Angrites are a rare group of achondrites consisting mostly of Al-Ti bearing diopside, hedenbergite, olivine, anorthite and troilite with minor traces of phosphate and metals. The group is named for the Angra dos Reis meteorite. They are the oldest igneous rocks, with crystallization ages of around 4.56 billion years. Angrites are subdivided into two main groups, the quenched and plutonic angrites. The quenched angrites cooled rapidly upon the surface of the angrite parent body (APB), whereas the plutonic angrites cooled slower, deeper in the crust. The APB is thought to have been a similar size to the asteroid 4 Vesta.