Material Index for the Spectroscopy Database

Material Index

Name	Formula	Classifications	Members	Image	Lines	Spectra	Techniques	Tags
Oldhamite	(Ca,Mg,Fe)S	Galena (group)	—	Oldhamite Dark grey grains, masses and tiny veins of oldhamite in calcite, from Lichtenberg Absetzer Mine (dump), Ronneburg U deposit, Gera, Thuringia, Germany. Ex Fritz Rüger collection. Field of view 1.5 cm. © Photo by Leon Hupperichs (via Wikimedia Commons), CC-BY-SA 3.0	2	0	CL/OM	Mineral, Sulphide
Olgite	(Ba,Sr)(Na,Sr,REE)₂Na(PO₄)₂	Minerals containing PO4	—	Olgite Very dark green crystals of the rare phosphate mineral olgite from the type locality in Karnasurt Mountain, Lovozero Massif, Kola Peninsula, Russian Federation © Photo by David Hospital (via Wikimedia Commons), CC-BY-SA 4.0	3	0	PL, PL/XL	Mineral, Phosphate , Orthophosphate
Oligoclase	(Na,Ca)(Si,Al)₄O₈	Plagioclase	—	Oligoclase Photograph of Oligoclase (var. sunstone, NMNH G3273) from the National Gem Collection, showing golden sheen. Specimen from Tvedestrand, Aust-Agder, Norway © Photo by Chip Clark, via Smithsonian National Museum of Natural History	14	1	EDS	Aluminosilicate , Variety
Olivine	(Mg,Fe^II)₂SiO₄	Nesosilicate	Liebenbergite, Tephroite, Glaucochroite, Kirschsteinite, Laihunite, Peridot, Calcio-olivine, Forsterite, Monticellite, Fayalite	Olivine Forsterite (var. peridot) olivine from St John's Island (Zagbargad), Red Sea, Egypt © Rob Lavinsky, iRocks.com – CC-BY-SA-3.0	3	0	Reflectance	Group , Silicate
Olympite	LiNa₅(PO₄)₂	Minerals containing PO4	—		1	0	PL	Mineral, Phosphate , Orthophosphate
Opal	SiO₂·nH₂O	Minerals containing H2O	—	Opal Dark Jubilee Opal specimen (318.44ct) from Coober Pedy, South Australia, Australia © Photo by Chip Clark, via Smithsonian National Museum of Natural History	19	1	CL	Mineral, Hydrated
Orthoclase	KAlSi₃O₈	K feldspar	—	Orthoclase Orthoclase specimen (27x17cm), from Minas Gerais, Southeast Region, Brazil © Photo by Didier Descouens (via Wikimedia Commons), CC-BY-SA 4.0	10	1	CL	Mineral, Aluminosilicate
Osmium	Os	—	—	Osmium Cluster of osmium crystals grown by chemical vapor transport © Image courtesy www.periodictable.ru, via Wikimedia Commons. CC-BY-3.0	16	1	SXES	Mineral , Metal , Element
Otavite	CdCO₃	Calcite (group), Minerals containing CO3	—	Otavite Otavide crystals (white), from Tsumeb Mine, Tsumeb, Otjikoto Region, Namibia © Photo by Christian Rewitzer (via Wikimedia Commons), CC-BY-SA 3.0	1	0	Unknown	Carbonate , Mineral