Larimar

Larimar is the pale blue, sky- or sea-coloured variety of pectolite, a calcium-sodium silicate mineral. Gem-quality material is mined commercially from just one place, the Barahona region in the south-west of the Dominican Republic. Its name joins the name of Larissa, the daughter of Miguel Méndez, who rediscovered the stone in 1974, with the Spanish word for “sea” (mar).

Jewellery: It is cut into cabochons, beads, rings and necklaces. It is mostly set in silver, and fine stones sometimes in gold. It is sold in the Dominican Republic and the Caribbean as a local jewellery and souvenir speciality. Care: According to GIA its blue colour is stable to light, but it reacts to irradiation and to the heat of a jeweller's torch, so care is needed during repairs.

It has a hardness of 4.5–5 on the Mohs scale. A fingernail cannot scratch it, but a steel knife can. Its specific gravity is 2.81–2.9 g/cm³.

Its best-known localities: Los Chupaderos, Barahona, Dominican Republic; Bahoruco Mountains, Barahona, Dominican Republic.

Blue ground with white, fibrous, radiating (fan-shaped) patterns; the colour ranges from pale sky blue to sea green. Its hardness is 4.5–5: a steel knife scratches it, but it cannot scratch glass, and harder stones such as quartz scratch it. It is translucent to opaque with a silky lustre. Genuine larimar has a refractive index of about 1.60 and a specific gravity of about 2.81; these values are used to tell imitations apart. Ceramic imitation: in 2013 GIA described a Chinese-made larimar imitation consisting of about 95 % aluminium oxide. Its refractive index was 1.53 and its specific gravity 1.87; under the microscope it showed white gas bubbles and concentrations of blue colour.

On the “street to diamond” value ladder it sits on step 6 of nine: Fine ornamental and collector stone. Its value depends on the intensity and vividness of the blue; sky-blue tones and strong contrast with the white pattern are sought. Stones free of cracks, solid and taking a good polish are worth more. Because it comes commercially from a single place, supply is limited, and since a ceramic imitation exists it matters that the seller states the stone is natural larimar.

In crystal-therapy circles larimar is called the “Atlantis stone” or “dolphin stone”; the name is said to go back to a “reading” by the medium Edgar Cayce about a blue stone that would be found in the Caribbean. Crystal-therapy practitioners claim that larimar opens the throat chakra and makes it easier to express feelings and thoughts. The same circles say larimar soothes anger and reduces fear, anxiety and stress. There is no scientific evidence that larimar opens chakras, improves mood or reduces anxiety; lasting anxiety and panic call for a doctor or a mental-health professional. The “Atlantis” link is only a story: the stone was rediscovered in the Dominican Republic in 1974, and its blue comes from copper replacing calcium in pectolite. This section reports beliefs; it is not health information. There is no scientific evidence for these claims and no stone replaces medical treatment.