D-Colour Natural IIa Diamond with Walstromite Inclusion
A diamond is proven to have a superdeep origin through an inclusion of CaSiO3-walstromite.
Update on the Rock Creek Sapphire Deposit
An overview of recently expanded sapphire production at the Gem Mountain mine near Philipsburg, Montana.
Summer 1990 Gem News International
A compilation of gem news from around the world, covering topics such as localities, unusual gem materials, market news, new products, discoveries, jewellery manufacturing techniques and industry trends.
Indian Ruby Mining
An overview of ruby mining in the southern Indian states of Tamil Nadu and Karnataka.
Large Oolitic Opal Block
The natural-colour oolitic opal is the largest of its type examined by GIA.
Natural Pipi Pearls from Tahiti
An overview of natural "pipi" pearls from French Polynesia.