Dendritic inclusions in a pinkish-purple sapphire are revealed with fiber-optic lighting.

Analyzes the substructures that cause the intense iridescence observed in “rainbow” hematite from Minas Gerais, Brazil.

A sapphire from Pailin, Cambodia, hosts inclusions that are unusual for this material.

Rare dissolution etch channels are seen in a natural diamond.

Alexey Burlakov shares insights on the current production of Russian demantoid and emeralds.

Characterizes diamonds with exceptionally rare natural green color, based on GIA’s extensive database of samples.

John Woodmark provides an update on the Ponderosa sunstone mine in Oregon.

A gemological investigation of the aquamarine that has emerged from northern Pakistan in recent years.

A new report from GIA's Bangkok laboratory,

A new report from GIA's Bangkok laboratory examines a set of 120 NBC samples stated to be of "Tahitian" origin.