Voudouris P. auteur aut IRD Mavrogonatos C. auteur aut IRD Graham I. auteur aut IRD Giuliani Gaston auteur aut IRD Tarantola A. auteur aut IRD Melfos V. auteur aut IRD Karampelas S. auteur aut IRD Katerinopoulos A. auteur aut IRD Magganas A. auteur aut IRD text journalArticle eng text/pdf reformatted digital access In the Hellenides Orogen, minerals of various gem quality occur in various rock types from mainly four tectono-metamorphic units, the Rhodope, Pelagonian, and the Attico-Cycladic massifs, and the Phyllites-Quartzites unit of Crete Island. In crystalline rocks, gemstones are related to both regional metamorphic-metasomatic processes (e.g., gem corundums, Mn-andalusite, thulite/clinothulite, spessartine, titanite, jadeite), and to the formation of late alpine-type fissures, such as, for example, quartz, albite, adularia and titanite. The Tertiary (and Mesozoic) magmatic-hydrothermal environments provide gem-quality sapphire, beryl, garnet, vesuvianite, epidote, fluorite, and SiO2 varieties. The supergene oxidation zone of the Lavrion deposit hosts gem-quality smithsonite and azurite. Coloration in the studied material is either due to various chromophore trace elements present in the crystal structure, or due to inclusions of other mineral phases. Future modern exploration methods combined with gemological investigations (such as treatment and faceting of selected stones), are necessary in order to obtain a better knowledge of the gemstone potential of Greece for its possible exploitation. specialized gemstones corundum beryl jadeitite garnet quartz varieties Greece GRECE 064 9 8 art. 461 [29 p.] 2019 https://www.documentation.ird.fr/hor/fdi:010076635 10.3390/min9080461 [F B010076635] https://www.documentation.ird.fr/hor/fdi:010076635 https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers19-09/010076635.pdf IRD - Base Horizon / Pleins textes 2019-10-14 2025-02-24 fdi:010076635 fre