Deltalumite
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Revision as of 10:46, 30 August 2022 by Apm (Talk | contribs) (Apm moved page Deltalumide to Deltalumite without leaving a redirect: misspelling)
A polymorph of leukosapphire.
This compound/material/gemstone is interesting because normally Al2O3 forms leukosapphire (corundum structure).
Al2O3 Deltalumite (δ form of corundum, polymorph of sapphire) – tetragonal – Mohs ?? (likely quite hard) – [1]