Tourmaline group · October birthstone
Tourmaline
The widest colour range of any gem family, from rubellite pink to Paraíba neon.
- Hardness
- Mohs 7.5
- Toughness
- Fair
- Daily wear
- Good for daily wear
- Price tier
- USD 100 to 5,000 (Paraíba: to 30,000+) per carat, fine quality
- Colours
- Pink (rubellite), Green, Neon blue (Paraíba), Watermelon, Blue (indicolite)
- Origins
- Brazil, Mozambique, Nigeria, Afghanistan
Tourmaline is a family of boron silicates that comes in more colours than any other gem: rubellite (pink to red), verdelite (green), indicolite (blue), bicoloured watermelon crystals and the copper-bearing Paraíba tourmaline, whose neon blue-green commands prices in the tens of thousands per carat. Most tourmaline is affordable, colourful and hard enough for regular wear.
How to buy tourmaline
Buy for colour and clarity; rubellites are often included and priced accordingly. For Paraíba, a laboratory report confirming copper content and origin is essential.
Treatments
Heating and irradiation are common; Paraíba-type stones are often heated.
Care
Warm soapy water; avoid ultrasonic for included stones and sudden heat.
Lore
Dutch traders used tourmaline crystals, which become electrically charged when warmed, to pull ash from their pipes.
