Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2020, 37(4), 344–346. http://doi.org/10.15506/JoG.2020.37.4.344 Celestine (or celestite, coelestite) is named after the...
Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2022, 38(1), 9–11. http://doi.org/10.15506/JoG.2022.38.1.9 Crocoite (PbCrO4) was first found in Russia in 1763, later in a...
Many fluorite prisms have been available for years. These are natural fluorite material shaped and polished like a hexagonal prism terminated by a pyramid and by either a second pyramide or a basal...
Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2020, 37(1), 7–9. http://doi.org/10.15506/JoG.2020.37.1.7 During the December 2019 Paris International Mineral & Gem...
Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2019, 36(8), 688–690. http://doi.org/10.15506/JoG.2019.36.8.688 Enstatite may display asterism with four, six or eight...
Zoisite is very famous in jewellery because of its violet-blue variety named tanzanite after its country of discovery, Tanzania. Zoisite is the orthorhombic polymorph of clinozoisite, a member of...
Recently, a kind of gray 'sunstone' entered the market, it is offered either as a sunstone, an aventurescent feldspar or the most frequently as an aventurescent quartz included of graphite. The...
Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2019, 36(7), 585–587. http://doi.org/10.15506/JoG.2019.36.7.585 Well-known amongst mineral collectors, zeolite minerals are...
Initially published as a Gem note in the Journal Of Gemmology of the Gem-A. 2019, 36(6), 501–503. http://doi.org/10.15506/JoG.2019.36.6.501 Hydroxylherderite [CaBePO4(OH,F)] is a phosphate mineral that forms a...
During 2018, deep blue spinels from Nigeria were availble. The four crystals samples of this material were provided by the gemstone dealer Walter Asikaro directly from Nigeria and were described in...