Larimar

Larimar is the trade name for a rare blue variety of the mineral pectolite, a sodium calcium silicate. Its serene sky-blue to blue-green color, marbled with white, is caused by copper substituting for calcium in the structure.

Unlike ordinary white or gray pectolite found in many places, blue larimar comes from only one place on earth: a small area in the Barahona Province of the Dominican Republic. This single-source rarity makes it a distinctive Caribbean gemstone.

The name combines "Larissa," the daughter of the man who popularized it, with "mar," the Spanish word for sea, reflecting its ocean-like color. It is sometimes called the dolphin stone or Atlantis stone.

Larimar forms in cavities and gas bubbles (vesicles) within volcanic basaltic rocks. Hot, mineral-rich hydrothermal fluids carrying the necessary elements, including copper, deposited blue pectolite within these voids as the lava cooled.

Over time, erosion freed larimar-bearing rock, and pieces were carried downslope and into rivers, eventually reaching the sea, which is why some larimar was first found as beach pebbles. The primary deposit is mined in the mountains of Barahona Province in the southwestern Dominican Republic.

The restricted geology, blue pectolite forming only where copper-bearing fluids met the right basaltic host, explains its single known source and limited supply.

Look for a sky-blue to greenish-blue stone with white, cloudy or web-like patterning, often resembling sunlit water. Larimar is translucent to opaque with a hardness of 4.5-5, so it scratches relatively easily, and has a vitreous to silky luster.

The needle-like, radiating fibrous structure of pectolite may be visible, and color can fade with prolonged sunlight and heat exposure. Streak is white.

Look-alikes include turquoise, amazonite, blue chalcedony and dyed howlite or imitations. Larimar's distinctive blue-and-white volcanic patterning and softer hardness help distinguish it; turquoise is more uniform and often greener, while dyed imitations may show unnatural, even coloring.

Larimar is almost exclusively a gemstone and lapidary material, cut into cabochons, beads and inlay for pendants, rings and earrings. Because it is moderately soft and its color can fade in sunlight, it is best in protected settings and kept out of prolonged direct light and heat.

It is a signature product of the Dominican Republic and a popular Caribbean souvenir and designer gem. Higher grades show intense, even blue with attractive white patterning.

Metaphysically, larimar is associated with calm, communication and the throat, and is marketed as a soothing "stone of the sea," though these claims are not scientific.