What is Larimar?
Larimar is the blue ornamental variety of pectolite, prized for its ocean-like colour, radiating texture and limited Dominican locality.
Mineralogy and crystal structure
Reference formula: NaCa2Si3O8(OH). Larimar is a trade and lapidary name for blue pectolite, not a separate mineral species. Copper-related colour is commonly discussed for the blue material, while the pectolite host is a triclinic inosilicate. The displayed structure is a representative pectolite model from COD. Larimar is classified with silicates and has a triclinic crystal system. Typical hardness is 4.5–5 on the Mohs scale and specific gravity is approximately 2.8–2.9.
Colour, lustre and habit
Typical colours include blue, blue-green, white, turquoise. The usual fibrous, radiating, massive habit and vitreous, pearly lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Larimar forms in or is associated with hydrothermal cavities in basaltic volcanic rocks and associated metamorphic zones. Important documented localities include the Dominican Republic, especially the Barahona region.
The blue stone with a single classic locality
Larimar is unusually easy to place in a collection: its soft Caribbean blue, white clouding and fibrous patterns immediately suggest the volcanic cavities of the Dominican Republic. Natural pattern and provenance matter more than perfectly uniform colour, which is why well-documented pieces command attention.
Collecting and care
Protect polished surfaces from scratches, heat and acids; avoid ultrasonic or steam cleaning and disclose the trade name together with pectolite when describing the material.
