Feature
Gems & Gemology, Fall 2001, Volume 37, No. 3
Pyrope from the Dora Maira Massif, Italy
Alessandro Guastoni, Federico Pezzotta, and Margherita Superchi, Francesco Demartin
Large pyrope crystals containing gem-quality portions have been collected since the early 1990s from the Dora Maira Massif, Western Alps, Italy. These crystals have yielded pale purple to purplish pink gemstones typically up to 1 ct. The chemical composition and physical properties compare favorably to those reported for near-end-member pyrope. Absorption spectra suggest that the color is related to Fe2+ and Mn2+. The pyrope formed in a mica schist-quartzite layer within Paleozoic basement rocks that underwent an Alpine high-pressure/low-temperature metamorphic event. The deposit appears extensive, but future production undoubtedly will be limited due to environmental restraints. Currently about 100 carats per year enter the marketplace.
