Nail Head Calcite | Tri-State matrix or Iron Pyrite is a

or Iron Pyrite is a pale brass-yellow iron sulfate (FeS2) mineral

Sodalite is typically a  royal blue mineral part of the feldspathoid group

earthy brown tones

With a Mohs hardness of 3–3

Nail Head Calcite | Tri-State matrix or Iron Pyrite is aThis specimen features sharp, golden nail head calcite crystals from the historic Tri State mining district of Missouri, Kansas, and Oklahoma. The distinctive flattened crystal habit gives the appearance of nail heads, a signature form from this region. Under ultraviolet light, the calcite fluoresces, adding an extra dimension to its natural beauty. A fine example of classic Tri State mineralogy and vintage American mining heritage. This item is 4. 5