As stated right here previously on our blog, October is truly the month so fun you can’t have just one…birthstone, that is! Or maybe it’s the month so nice, you have to gem it twice. Or maybe it’s the month of clones, so it needs TWO stones.
But we digress.
Tourmaline is a gorgeous gem that comes in a variety of colors from deep blues and greens to lighter greens and pink. Whereas the other October birthstone, opal, is a softer mineral (5.5 – 6 on the Mohs scale), tourmaline is a bit more robust with a hardness of 7 to 7.5 on the Mohs scale…about equivalent to the hardness of citrine and other varieties of quartz.
Here are 10 things you may not know about this October birthstone…
1. Tourmaline comes in three main species: schorl, dravite and elbaite.
2. Schorl is black or brownish-black, dravite color ranges from a dark yellow to a brownish-black and elbaite comes in a variety of colors from colorless to blue, green and pinkish-red.
3. In the 1600’s when the Dutch East India company was bringing gem tourmalines of various colors from Sri Lanka to Europe, many of the colored stones were believed to be zircons. It wasn’t until around 1703 that it was discovered that the brown/black schorl variety was indeed the same mineral as these beautiful, colored and transparent gems.
4. Tourmaline has pyroelectric properties, which basically means tourmaline crystals are naturally electrically polarized and actually contain electric fields as a result. Because of this, it has been referred to as the “Sri Lankan Magnet” due to its ability to both attract and repel hot ashes. Interestingly, tourmaline was once used to clean dust out of pipes.
5. Tourmaline has often been confused with other gemstones. From the 1600’s when many colored tourmalines were mistaken for zircon to 17th century crown jewels that were originally believed to be rubies. Deep green gem tourmalines mined in Brazil are still referred to by some as Brazilian emeralds, though it is known that they are tourmalines. This is a little fact to also keep in mind (mined?) when buying jewelry, as these names can cause confusion (another example is that sometimes smoky quartz is sold as “smoky topaz”).
6. In 1989, a group of prospectors discovered what are regarded as the finest tourmaline crystals ever found in a small mountain range in the state of Paraiba in South America. Due to the presence of copper, the stones have a vivid, bright turquoise color and have been valued at over $5,000 per carat.
7. Tourmalines are considered to be a “cognitive gem,” as they are believed to help increase one’s self-confidence and psychic energies, improve one’s ability to understand and aid in both communication and concentration.
8. One of the most unique, treasured and beautiful of tourmaline varieties is the watermelon tourmaline. These tourmalines have a green or bluish-green outside color with a core of pink or reddish-pink. Tourmalines also occur in other bi-colored varieties, but the watermelon tourmaline is the most sought-after color combo.
9. The dravite species of tourmaline is named after the Drave district of Carinthia where it was originally found, while the elbaite species is named after the island of Elba, Italy.
10. The elbaite species of tourmaline encompasses the different colored varieties popular as gemstones: colorless (achroite), red/pinkish-red (rubellite), green (verdelite, aka Brazilian emerald), light blue/bluish-green (indicolite).