Larimar Identification Guide
How to identify larimar, the blue Dominican pectolite, by its sky-blue color and white web-like patterning.
Read the full Larimar encyclopedia entry →
What Larimar Looks Like
Larimar is the trade name for a rare blue variety of the mineral pectolite (a sodium-calcium silicate). Its signature look is a soft sky-blue to turquoise or green-blue color marbled with white, gray, and sometimes reddish web-like or "turtle-shell" patterning. The blue is caused by copper substitution. It is translucent to opaque with a vitreous to silky luster, and polished pieces often show a watery, sea-foam appearance. Fibrous, radiating internal structure is typical of pectolite.
Step-by-Step Field ID Checklist
- Look for the blue-and-white pattern - irregular white veining over sky-blue, like sunlight on water.
- Note translucency and a soft, watery glow.
- Check the fibrous structure - radiating, silky needles under magnification.
- Test hardness - Mohs 4.5-5; a steel knife will scratch it (handle carefully).
- Consider provenance - true larimar is Dominican; this strongly supports identification.
Key Diagnostic Tests
- Mohs hardness 4.5-5: Relatively soft - scratched by a knife and quartz; rules out harder blue stones.
- Fibrous/radiating habit: Characteristic of pectolite.
- Streak: White.
- Specific gravity ~2.7-2.9.
- No acid reaction (silicate); not magnetic.
- Color stability: Natural larimar's blue may fade with prolonged sunlight/heat - a property dyed imitations don't share consistently.
Common Look-Alikes and How to Tell Them Apart
- Turquoise: Often more uniform robin's-egg blue with brown/black matrix veins; turquoise is a phosphate, slightly harder (5-6), and lacks larimar's fibrous radiating texture.
- Amazonite: Green-blue feldspar with a gridded white pattern but feldspar cleavage and hardness 6-6.5.
- Chrysocolla / gem silica: Copper-blue but often glassier (gem silica is hard, 7) or earthier; larimar's web pattern and softer hardness differ.
- Dyed howlite or magnesite ("fake larimar"): Dye pools in cracks, color is too even, and acetone may lift dye; lacks fibrous pectolite structure.
- Hemimorphite: Brighter blue, botryoidal, different habit.
Where Larimar Is Found
Larimar is found in essentially one place on Earth: the Barahona Province of the southwestern Dominican Republic, where it fills cavities in basaltic volcanic rock. Its single-source rarity is itself a strong identification clue.
Frequently asked questions
How can you tell if larimar is real?
Real larimar is blue pectolite with sky-blue color marbled by white web-like patterning, a hardness of only 4.5-5 (scratched by a knife), a fibrous radiating structure, and Dominican origin. Dyed imitations show color pooling in cracks and lack the fibrous texture.
What does larimar look like?
A soft sky-blue to turquoise stone marbled with white, gray, and sometimes reddish web or turtle-shell patterning, with a watery, sea-foam appearance.
Larimar vs turquoise - what's the difference?
Turquoise is a phosphate with more uniform blue and brown/black matrix veins, while larimar is a fibrous blue pectolite with distinctive white web patterning and is slightly softer.
Where does larimar come from?
Larimar is found in only one location in the world - the Barahona Province of the southwestern Dominican Republic - where it occurs in cavities within basaltic volcanic rock.
Does larimar fade in sunlight?
Natural larimar's blue can fade with prolonged exposure to sunlight and heat, so it is best kept out of intense direct light.
Larimar identified by the community
Recent Larimar specimens identified with Rock Identifier.
