Powellite

Rarity: Common

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At a glance

Class

Notion

Domain

Science and technology

In collections

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What Wikipedia says

Powellite is a calcium molybdate mineral with formula CaMoO4. Powellite crystallizes with tetragonal – dipyramidal crystal structure as transparent adamantine blue, greenish-brown, yellow-to-grey typically anhedral forms. It exhibits distinct cleavage, and has a brittle-to-conchoidal fracture.

Excerpt from the Wikipedia article “Powellite”, under the CC BY-SA 4.0 license. Read the article on Wikipedia

Image: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons.