Larimar

Larimar is the blue gem variety of pectolite, a sodium calcium silicate mineral that’s common enough in its ordinary, non-gem forms but almost never found in the sky-blue to blue-green color that makes larimar distinctive. What makes it genuinely unusual is where it comes from: gem-quality material has only ever been documented in commercial quantities in one place on Earth, the Barahona province of the Dominican Republic — a single-locality rarity in the same category as tanzanite, even though larimar trades at a fraction of tanzanite’s price because demand and market positioning differ so much between the two.

The name itself has an unusually well-documented, recent origin for a gemstone. It was formally identified and named in 1974 — combining “mar,” Spanish for sea, a reference to its color, with “Larissa,” the daughter of one of the people involved in bringing the stone to wider attention. Most gemstone names trace back centuries or further and their exact origins are genuinely uncertain; larimar’s story is thoroughly documented because it’s recent.

At Mohs 4.5 to 5, larimar sits in a similar durability range to turquoise — softer than quartz, and soft enough that it’s typically cut as a cabochon rather than faceted, both to protect the stone and to show off its color and any white or gray veining running through it, similar in spirit to how malachite is usually cut for the same reasons. It crystallizes in the triclinic system, and like turquoise and malachite, gem material is found as a compact mass rather than as large individual crystals.

Larimar doesn’t appear on any of the historical or modern monthly birthstone lists, or on either zodiac system, tracked on this site — its single-locality origin and recent discovery mean it postdates every one of the birthstone systems documented here.