HauyneLocality: Niedermendig Mayen, Eifel, Germany.Hauyne shares with Lazurite the same chemical for

Hauyne

Locality: Niedermendig Mayen, Eifel, Germany.

Hauyne shares with Lazurite the same chemical formula but with a variation of the sulfide over the sulfate. Hauyne has the sulfate dominating, whereas Lazurite has the sulfide dominating. Much of the known Lazurite material is actually sulfate-dominating, which means it is in fact Hauyne and not Lazurite.  

Reference: [1]

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