It is rarely a primary mineral in copper deposits, and is even less likely to be found as a volcanic sublimate.

As a primary mineral, the formation of covellite is restricted to hydrothermal conditions.

Illite originates from the modification of mica, a primary mineral.

It is often found together with montmorillonite and its primary minerals.

As the primary minerals in soil parent material weather, the elements combine into new and colorful compounds.

In many of them there is no reason to doubt that the scapolite is a primary mineral.

The top layers of the enamel's primary mineral, hydroxylapatite, are converted into the more robust fluorapatite.

It is also the primary mineral in metamorphic marble.

Calcium is the primary mineral needed for building and maintaining strong bones.