Mineral · Zeolite group
Stilbite
NaCa4(Si27Al9)O72·28H2O
Stilbite (stilbite-Ca) is the commonest zeolite, forming peach, white or salmon sheaf-like ('bow-tie') aggregates in the Deccan basalts of India (Pune, Nashik, Jalgaon), Iceland, Nova Scotia and the Skye basalts. Indian stilbite on apophyllite and chalcedony is cheap and plentiful. The pearly lustre and sheaf habit identify it.
| Formula | NaCa4(Si27Al9)O72·28H2O |
|---|---|
| IMA status | approved |
| Crystal system | Monoclinic |
| Mohs hardness | 3.5–4 |
| Group | Zeolite group |
| Type locality | None |
| Streak | White |
| Specific gravity | 2.2 |
| Reference list | IMA List of Minerals (RRUFF) — verify formula and status against the current list |
Fakes and treatments
Indian zeolite groups are sometimes reassembled or glued; check the base.
Elsewhere
Cite this article
Stratum Study. "Stilbite" (Mineral). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/minerals/stilbite. Accessed 2026-09-20.
@misc{stratum-stilbite,
title = {Stilbite},
author = {{Stratum Study}},
howpublished = {\url{https://stratum.black/study/minerals/stilbite}},
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.