What is Jonesite?
Jonesite is a rare barium titanosilicate with a porous framework, a collector mineral that links zeolite-like architecture with titanium chemistry.
Mineralogy and crystal structure
Reference formula: Ba2(K,Na)[Ti2(Si5Al)O18](H2O)n. Jonesite has a monoclinic porous silicate structure with barium, alkali cations, titanium and water in the framework environment. Its formula is commonly written with variable water and mixed alkali occupancy. Jonesite is classified with silicates and has a monoclinic crystal system. Typical hardness is 4–5 on the Mohs scale and specific gravity is approximately 3.0–3.2.
Colour, lustre and habit
Typical colours include colourless, white, pale yellow. The usual tabular, prismatic, granular habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Jonesite forms in or is associated with alkaline igneous rocks, cavities and late hydrothermal alteration zones. Important documented localities include Mont Saint-Hilaire in Canada and other alkaline-rock localities.
A specialist mineral with a framework story
Jonesite is a strong addition to a rare-mineral cabinet because its chemistry is immediately distinctive: barium, titanium, alkali metals and a porous silicate framework in one small specimen. It rewards a label that tells the structural story.
From crystal form to curiosity
Collectors often value Jonesite as a reminder that pale crystals can hide complex architecture. Any symbolic interpretation is personal and optional; the measurable fascination is its porous titanosilicate framework.
Collecting and care
Protect small crystals and avoid heat or strong chemicals that may affect hydrated framework components.
