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Tourmaline

· 1 min read · Materials

Tourmaline is a family of gems in every color (7-7.5 on Mohs), with varieties such as watermelon and Paraíba; it is the October birthstone.

Illustration: Tourmaline

Tourmaline is not one stone but a mineral family with an almost endless color range: pink, green, blue, black, colorless and bicolor. It is the October birthstone together with opal.

Properties #

  • Composition: complex borosilicate of aluminum and other metals.
  • Hardness: 7 to 7.5 on the Mohs scale.
  • Color: every color; watermelon (pink and green), rubellite (pink to red), indicolite (blue) and Paraíba (neon blue) are famous.
  • Origins: Brazil, Mozambique, Nigeria, Afghanistan and the USA.
  • Treatments: some are heated or irradiated.

Uses in jewelry #

  • Colorful rings, earrings and pendants.
  • Cabochons and faceted cuts.
  • Studio jewelry.

Pros and cons #

Advantages #

  • A huge variety of colors.
  • Hard enough for everyday wear.
  • Prices vary widely.

Limitations #

  • Varieties such as Paraíba are very expensive.
  • Some are fragile because of internal fractures.
  • Attracts dust when heated (pyroelectricity).

Care and cleaning #

  • Clean with lukewarm water and mild soap.
  • Avoid sudden temperature changes.
  • Check for fractures before using ultrasonic.

See also #

This entry was drafted with the help of AI and is pending review by the author.