Mineralpedia Details for Oneillite
Oneillite
Named for John Johnston O’Neill, as a geologist with the Geological Survey of Canada and Professor of Geology and Dean of Science and Dean of Engineering at McGill University in Montreal, Canada. The type and only locality for Oneillite is at the Poudrette quarry at Mont Saint-Hilaire in Quebec, Canada where it is found at a contact between a vein of albite and the nepheline syenite. Oneillite occurs as yellow to brown anhedral grains.
Ref. Minerals and their Localities, Bernard, J.H. and Hyršl, J. (2004)
IMA/CNMNC List of Mineral Names (2009) and Canadian Mineralogist 37 (1999), 1295
- Formula
- Na15Ca3Mn3Fe3Zr3Nb(Si25O73)(O,OH,H2O)3(OH,Cl)2
- Crystal System
- Trigonal
- Crystal Habit
- Anhedral Grains
- Cleavage
- None, None, None
- Luster
- Vitreous (Glassy)
- Color
- yellowish brown
- Streak
- white
- Class
- Trigonal - Pyramidal
- Fracture
- Brittle - Uneven
- Hardness
- 5-6
- WebMineral
- View Oneillite
- Mindat
- View Oneillite
Oneillite from Poudrette quarry, Mont Saint-Hilaire, Montérégie, Québec, Canada
Golden brown anhedral crystals to 1mm.
Click thumbnail images for larger view.
Oneillite from Poudrette quarry, Mont Saint-Hilaire, Montérégie, Québec, Canada
- Special Info
- Type & Only Locality
Brownish orange crystal grains encompassing an area to 5mm across.
Click thumbnail images for larger view.
