Dolni Okol, Sofiya Oblast (Sofia Oblast), Bulgaria

Emerald mineralization area near the Urdina Lakes, in the north-western part of the Rhodopes. A Proterozoic metamorphic rock sequence, which consists of micaceous and amphibole-biotite gneisses, amphibolites, and marbles with small lenticular bodies of serpentinized ultramafic rocks, locally altered to amphibole-chlorite and talc-chlorite schists. The metamorphic rocks ae cut by granite pegmatites.

Emeralds in the form of well-shaped prismatic crystals, 0.4 to 1.5 cm long have been found only in the phlogopite-oligoclase bodies. The density is 2.694 g/cm³.

Bluish green and light green almost colourless beryls, apatite, margarite, chrysoberyl, allanite, and lesser amounts of fuchsite, rutile, bismutite, fine-scaly muscovite and fine-grained quartz occur with the emerald.

Ref: E.Ya. Kievlenko, Geology of gems, 2003, p. 85

Gemstone List


Copyright © Jolyon & Katya Ralph 1993-2018. Site Map. Locality, gem & photograph data are the copyright of the individuals who submitted them. For more information please contact the . Gemdat.org is an online information resource dedicated to providing free gemmological information to all.