True Colours of “Dalmatian Jasper”
Discusses the mineralogical composition and provenance of this spotted decorative gemstone.
Variscite from Central Tajikistan: Preliminary Results
A look at the gemmological properties and chemical composition of this light blue to light green to green gem material, which is suitable for cabochon cutting.
Star of the South: A Historic 128 Ct Diamond
This article presents the first complete gemmological characterisation of the historic 128.48 ct Brazilian diamond known as the Star of the South.
Discovery and Mining of the Argyle Diamond Deposit, Australia
Australia’s Argyle mine has set records for volume since its establishment in 1983, and is additionally noted for its rare pink diamonds.
Ammolite: Iridescent Fossilised Ammonite from Southern Alberta, Canada
Ammolite is a form of aragonite that is obtained from vivid iridescent fossilised ammonite shells mined in Alberta, Canada.
Gem-quality haüyne from the Eifel district, Germany
Haüyne is a rare mineral and an extremely rare gemstone. Recently, the authors studied a large number of faceted haüynes from the Eifel district of Germany.
Gem-Quality Green Zoisite
A new transparent, gem-quality green zoisite has been discovered in the Merelani Hills of mineral-rich Tanzania.
Sunstone Labradorite from the Ponderosa Mine, Oregon
The Ponderosa mine is now producing commercial quantities of the gem-quality labradorite feldspar known as sunstone.
New Rubies from the Morogoro Area, Tanzania
The authors present the mineralogical and gemmological properties of rubies found recently in the Morogoro area of Tanzania that have many features in common with rubies from Myanmar (Burma) and other comparable marble-type deposits.
Rubies and Fancy Sapphires from Vietnam
Gem-quality rubies and pink to purple sapphires are being recovered from the Luc Yen and Quy Chau mining regions of Vietnam.