Crystals & Stones

Ettringite specimen from N'Chwaning Mines, South Africa; photo by Didier Descouens, CC BY-SA 3.0 — Roosters Peacock crystal guide
Ettringite: The Stone of Structure, Patience & Clear Formation
Ettringite is a highly hydrated calcium aluminum sulfate mineral in the trigonal system, typically forming delicate prismatic or fibrous crystals and also occurring as a cement-hydration product. Explore its mineral... Read more...