Ametista do Sul amethyst geode mines

Where: Rio Grande do Sul · South America · approx. -27.36, -53.18 (vicinity only)

Why this spot: Cretaceous Parana basalt vugs

What turns up: Large amethyst geodes, calcite, gypsum; the classic Brazilian amethyst

Access: Prohibited / view only.

Underground amethyst mines are private commercial operations; specimens bought, tours available

Satellite view, historic-map overlays, tide/flow context and field notes are in the app. Exact research detail is part of Pro.