Mineral · Pyroxene group
Augite
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6
Augite is the common black pyroxene of basalts and gabbros, found as stubby eight-sided prisms weathered out of tuffs at Vesuvius, the Eifel and Bohemia and in Arizona and Oregon volcanic fields. It is inexpensive and mainly a reference specimen for the pyroxene group. It is distinguished from hornblende by its near-90° cleavage angle.
| Formula | (Ca,Na)(Mg,Fe,Al,Ti)(Si,Al)2O6 |
|---|---|
| IMA status | grandfathered |
| Crystal system | Monoclinic |
| Mohs hardness | 5.5–6 |
| Group | Pyroxene group |
| Type locality | None |
| Streak | Greenish grey |
| Specific gravity | 3.4 |
| Reference list | IMA List of Minerals (RRUFF) — verify formula and status against the current list |
Elsewhere
Cite this article
Stratum Strata. "Augite" (Mineral). Stratum Strata pack 2026.09, as of 2026-09-21. https://stratum.black/strata/minerals/augite. Accessed 2026-09-21.
@misc{stratum-augite,
title = {Augite},
author = {{Stratum Strata}},
howpublished = {\url{https://stratum.black/strata/minerals/augite}},
year = {2026},
note = {Mineral article, Stratum Strata pack 2026.09, as of 2026-09-21; sources: stratum, wikidata, commons. Accessed 2026-09-21.}
} Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.