Nonfading Maxixe-Type Beryl?
A "nonfading" specimen was examined and proved to be the typical fading Maxixe-type deep blue beryl.
Update on Diffusion-Treated Corundum: Red and Other Colors
Blue diffusion-treated sapphires have become a subject of considerable controversy since their introduction in significant quantities a few years ago.
Treated-Color Pink-To-Red Diamonds from Lucent Diamonds Inc.
Using a multi-step process, Lucent Diamonds has developed a new treatment process for certain natural diamonds that creates colors from pink-purple through red to orangy brown.
Dreamy Drusy: Minute Crystals Shimmer in Dramatic Designs
Drusy jewelry has surged in popularity in recent years. Celebrities wear it on the red carpet and designers clamor for it at gem shows.
Gemstones with Alexandrite Effect
The term "alexandrite effect" refers to the apparent change of color in certain minerals from blue-green or greenish violet in daylight to red or reddish violet in incandescent light.
Opal from Queretaro, Mexico: Occurrence and Inclusions
An examination of play-of-color opal from Mexico and its variety of inclusions.
Gota de Aceite: Nomenclature for the Finest Colombian Emeralds
The finest and rarest emeralds are sometimes said to have an optical effect called gota de aceite.
Sunstone Labradorite from the Ponderosa Mine, Oregon
The Ponderosa mine is now producing commercial quantities of the gem-quality labradorite feldspar known as sunstone.
Optimizing Face-Up Appearance in Colored Gemstone Faceting
How contrast patterns can increase perceived brightness and optimize a gemstone's appearance.
Synthetic Star Sapphires and Rubies Produced by Wiede’s Carbidwerk, Freyung, Germany
Details the process used by Wiede’s Carbidwerk to produce star synthetic corundum from the mid-1950s through the 1970s.