Bicolor Double-Eye Tourmaline
A tourmaline displaying different colors of chatoyancy on opposite sides of a double cabochon is examined.
Unusual Pink Sapphire Bead
A pink sapphire bead with drill holes revealing ruby fragments is examined.
Iridescent Musgravite
A musgravite specimen’s inclusions result in an optical phenomenon unusual for the material.
Intense Blue Diamond with Very High Boron Concentration
A natural Fancy Intense blue diamond submitted to the New York lab shows the highest boron concentration ever reported in a natural specimen.
Blue Chalcedony Partially Filled with Epoxy Resin
A carving identified as blue chalcedony shows evidence of epoxy resin treatment.
Digital Photomicrography for Gemologists
A guide to capturing gem inclusion scenes using practical equipment and techniques and the appropriate image-refining software.
Rubies and Sapphires from Snezhnoe, Tajikistan
This large marble-hosted occurrence in the Pamir Mountains is a potentially productive source of corundum, including ruby with a bright red color reminiscent of “pigeon’s blood” Burmese rubies.
Dual-Color Double Stars in Ruby, Sapphire, and Quartz: Cause and Historical Account
Examines a form of asterism comprising two six-rayed stars, one white and one that exhibits the stone’s bodycolor. Firsthand accounts and a survey of patent documents reveal that diffusion has been used to create or enhance this optical phenomenon in synthetic and possibly natural corundum since the 1950s.
Introduction to the Micro-World of Gems
G&G’s new column takes a closer look at the hidden wonders found in gemstones.
Books: Imperial Jade of Burma and Mutton-Fat Jade of India
Review of S.K. Samuels’s Imperial Jade of Burma and Mutton-Fat Jade of India: Mining, Trade, and Use from Antiquity to the Present.
Books: Collector’s Guide to the Zeolite Group
Review of Collector’s Guide to the Zeolite Group, by Robert J. Lauf.
Books: I Love Those Earrings: A Popular History from Ancient to Modern
Review of I Love Those Earrings: A Popular History from Ancient to Modern, by Jane Merrill with Chris Filstrup.
Books: Imperial Jade of Burma and Mutton-Fat Jade of India
S.K. Samuel著 Imperial Jade of Burma and Mutton-Fat Jade of India: Mining, Trade, and Use from Antiquity to the Present（ビルマのインペリアル ジェードとインドの羊脂玉：採鉱と売買、古代から現代までの用途）の書評
Cat’s-Eye Calcite from Pakistan
Diamond-Bearing Eclogite Xenoliths from the Ardo So Ver Dykes
Mineralogical examination of diamond-bearing material from South Africa reveals the specimens to be eclogite xenoliths.
