Gemological Characterization of Sapphires from Yogo Gulch, Montana
A look at the mining and distinguishing characteristics of this naturally vibrant blue sapphire.
Black Diamonds from Marange (Zimbabwe): A Result of Natural Irradiation and Graphite Inclusions
Characterizes a suite of 40 natural brown to black diamonds from this deposit so that they can be distinguished from suspected treated black diamonds.
Perettiite-(Y) and Tusionite Inclusions in Phenakite from Myanmar
Seldom-seen inclusions are found in a host material that is rare in its own right.
Star Spinel with Four and Six Rays
A cabochon displaying asterism is found to be an untreated spinel with two different stars.
Mushroom in Copal
A Mexican copal plays host to a well-preserved mushroom.
Merelaniite Inclusions in Tanzanite
A recently identified mineral is found, in whisker-like form, in a gem-quality tanzanite host.
Microlite Crystals in Topaz from Pakistan
Aesthetically pleasing inclusions are found in topaz from Pakistan’s Shigar Valley.
A Horse-Shaped Inclusion in Pink Sapphire from Mozambique
Microscopic examination of a Mozambican pink sapphire reveals an inclusion with a surprising shape and composition.
Digital Photomicrography for Gemologists
A guide to capturing gem inclusion scenes using practical equipment and techniques and the appropriate image-refining software.
Update on Russian Demantoid Production
Alexey Burlakov shares insights on the current production of Russian demantoid and emeralds.