Mineral · Rutile group
Rutile
TiO2
Rutile is titanium dioxide, forming red-brown to black prismatic crystals with adamantine lustre at Graves Mountain (Georgia), the Alps and Brazil, and the golden needles inside 'rutilated quartz'. Rutile epitaxial on hematite from Brazil (Novo Horizonte) makes spectacular star-shaped specimens. It is the commonest of the three TiO2 polymorphs.
| Formula | TiO2 |
|---|---|
| IMA status | grandfathered |
| Crystal system | Tetragonal |
| Mohs hardness | 6–6.5 |
| Group | Rutile group |
| Type locality | None |
| Streak | Pale brown to yellow |
| Specific gravity | 4.25 |
| Reference list | IMA List of Minerals (RRUFF) — verify formula and status against the current list |
Elsewhere
Cite this article
Stratum Study. "Rutile" (Mineral). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/minerals/rutile. Accessed 2026-09-20.
@misc{stratum-rutile,
title = {Rutile},
author = {{Stratum Study}},
howpublished = {\url{https://stratum.black/study/minerals/rutile}},
year = {2026},
note = {Mineral article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, wikidata, commons. Accessed 2026-09-20.}
} 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.