- Formula
- NaCa2Si3O8(OH)
- Rarity
- Uncommon
- Stability
- Moderately Stable
- Collector interest
- Niche Interest
- Classification notes
- Pectolite is a calcium sodium inosilicate mineral with the formula NaCa₂Si₃O₈(OH). Its most famous variety is larimar, a rare blue form found almost exclusively in the Dominican Republic.
Stability
Physical Stability: Pectolite is relatively brittle and has perfect cleavage, meaning it breaks easily. It scores about 4.5–5 on the Mohs scale, so it's not ideal for wear in jewelry unless protected.
Chemical Stability: It is not highly reactive, but like many silicates, can be mildly affected by acids and prolonged water exposure. Larimar, for instance, may show surface dulling or etching if exposed to chemicals or harsh conditions.
Rarity
As a species: Pectolite itself is not rare and occurs in many localities worldwide, including the U.S., Canada, Italy, and Russia.
As a crystal specimen: Well-formed, translucent to transparent crystals are uncommon and can be highly sought after by collectors. Most pectolite is fibrous or massive.
Larimar (blue variety): Very rare, found almost exclusively in a single locality in the Barahona province of the Dominican Republic. The intense blue coloration is due to copper substitution and is highly prized.
