Gem-quality, colorless, facetable petalite is rare and desirable to collectors. More so if the stones are large and free of […]

Perthite is a blend of microcline, albite and oligoclase. It is usually brown and white. May have gold or white

Peristerite is primarily oligoclase with a complex mixture of feldspars. It has iridescence that is either blue or white.

The modern August birthstone, peridot has been prized as a jewelry stone since ancient times. Always green in color but

Periclase has been synthesized in large masses in the laboratory, but these have no market significance. A faceted natural periclase

Pentlandite resembles other yellowish metallic minerals and is cut by collectors as a curiosity. The cut stones are quite attractive

Fibrous pectolite has long been a curiosity for gem collectors. Compact material can make wonderful cabochons, and transparent crystals are

Discover everything about pearl value, types, and care in our comprehensive guide. Learn to evaluate pearl quality, understand differences between

More well-known as rare inclusions in emeralds, parisite crystals are usually small and seldom faceted.

The amphibole group is very large and extremely complex and contains numerous distinct species that vary subtly in chemistry and