Gem-Quality Red Beryl from the Wah Wah Mountains, Utah
The unique mineralogical and gemological character of gem-quality red beryl from Utah.
The Seven Types of Yellow Sapphire and Their Stability to Light
Acicular Troughs Coincident with Green Stains on Rough Diamond Surface
The author acquired an alluvial rough diamond from Guyana showing unique surficial features that do not appear to have been documented elsewhere.
The Hidden Beauty of Amber: New Light on an Old Subject
The surprising inner world of inorganic inclusions in amber is explored through the use of polarized light and microscopic techniques.
Natural Radioactivity in Select Serpentinite-Related Nephrite Samples: A Comparison with Dolomite-Related Nephrite
Uses gamma-ray spectrometry to directly measure internal radioactivity in green nephrite from deposits in Poland, Russia, Canada, and New Zealand.
A New Method for Determining Gem Tourmaline Species by LA-ICP-MS
Presents a simplified but comprehensive classification of gem tourmaline species based on quantitative measurement of six common major elements.
Etch Marks, Negative Crystals, and Etch Tubes in Spinel from Madagascar
A spinel from Madagascar, mixed in with a parcel of blue sapphire, exhibited an array of internal features.
YAG with Flux-Filled Fingerprints
The author recently examined a 3.58 ct yellowish green yttrium aluminum garnet, a manufactured product known in the trade as “YAG,” that contained numerous large flux-filled fractures.
Microscopic Shells in Natural Pearls from Pinctada radiata
Two pearls from Bahrain containing minute shells are examined at GIA’s Mumbai laboratory.
Plastic Deformation: How and Why Are Most Diamonds Slightly Distorted?
“Diffusion Ruby” Proves to be Synthetic Ruby Overgrowth on Natural Corundum
A relatively new production of red corundum, reportedly from Bangkok, has been offered for sale in recent years.
New Emerald Locality in Southern California
Located about 60 miles east of San Diego, a new emerald deposit has been discovered in the Julian Mining District.
An Interesting Rose Quartz from Madagascar
A new find of rose quartz from Madagascar contained some unusual inclusions.
A Pearl Identification Challenge
Two pearls presented a unique challenge, as testing at three different gemological laboratories could not conclusively identify them as natural or cultured, determine a freshwater or saltwater growth environment, or specify the producing mollusk.
15.53 ct Pearl Discovered in Edible Oyster from the Ostreidae Family
A large natural pearl discovered in an edible oyster offers insight to the scientific pearl community.
“Gran Dama” Brooch Featuring Large Melo Pearl
The centerpiece of this brooch is a 98.67 ct Melo pearl, believed to be one of the world's largest.
Faceting Transparent Rhodonite from Broken Hill, New South Wales, Australia
Transparent rhodonite is considered one of the most difficult of all gems to facet because of its perfect cleavage and brittle, uneven fracture.
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