Larimar

Larimar is a blue variety of the mineral pectolite, found in only one location on Earth - the mountainous Barahona Province of the Dominican Republic. While pectolite itself is a relatively common mineral (typically white to gray), the blue variety colored by copper substitution is unique to this single locality.

Larimar formed within volcanic rock - specifically in cavities and fractures within basaltic andesite flows. Hot, copper-bearing hydrothermal fluids deposited pectolite in these spaces, and the copper incorporated into the crystal structure produced the distinctive blue color. The deeper the blue, the higher the copper content.

The stone was officially 'discovered' in 1974 by Miguel Mendez and Peace Corps volunteer Norman Rilling, though local indigenous Taino people had known about blue stones in the region long before. Mendez named it by combining his daughter's name (Larissa) with the Spanish word for sea (mar). Mining is done by hand in small, artisanal operations in steep mountain terrain.

Larimar is identified by its distinctive Caribbean blue color with white marbling patterns - it genuinely looks like tropical water seen from above. At hardness 4.5-5, it's moderately soft. The white patterns are areas of lower copper content within the pectolite.

Distinguish from turquoise (different veining pattern, different blue tone, harder), blue chalcedony (no white marbling), and hemimorphite (different crystal structure, often more green). Larimar's white swirled patterns within the blue are its most distinctive visual feature.