What is Olenite?
Olenite is a tourmaline-group mineral rich in aluminium and boron, interesting to collectors for its complex chemistry and pegmatite setting.
Mineralogy and crystal structure
Reference formula: NaAl3Al6(BO3)3Si6O18(OH)4. Olenite belongs to the tourmaline supergroup, where substitutions and vacancies produce broad chemical variation. The formula is an idealised representation, not a complete analysis of every tourmaline crystal. Olenite is classified with silicates and has a trigonal crystal system. Typical hardness is 7–7.5 on the Mohs scale and specific gravity is approximately 3.1–3.3.
Colour, lustre and habit
Typical colours include blue, violet, pink, brown, black. The usual prismatic, acicular, massive habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Olenite forms in or is associated with boron-rich granitic pegmatites and hydrothermal alteration zones. Important documented localities include Finland, Russia, Canada, Brazil and other boron-rich pegmatite districts.
Tourmaline chemistry in an aluminium-rich form
Olenite shows why tourmaline is a mineralogical universe of its own: a durable trigonal framework can host a remarkable range of elements and colours.
Collecting and care
Protect from strong impact and heat; clean gently and retain matrix and locality information.
