Tourmaline

Tourmaline is a precious gemstone known for its wide range of colours, from vibrant pinks and greens to deep blues and even bi-coloured varieties such as watermelon tourmaline. It is a durable mineral with excellent brilliance, making it a popular choice for custom jewellery. Tourmaline is also known for its unique ability to become electrically charged when heated or rubbed, attracting dust and small particles.

Chemical Composition: Complex boro-silicate of aluminium, magnesium and iron

Crystal System: Triagonal

Refractive Index: 1.62 to 1.65

Specific Gravity: 3.0 to 3.1

Double Refraction: 0.014 to 0.021

Mohs Hardness: 7 - 7.5

Lustre: Vitreous

Tourmaline is found in many countries, with major sources including Brazil, Afghanistan, Madagascar, Nigeria, Sri Lanka and the United States. Some of the most famous tourmalines come from Brazil, particularly the bright neon Paraiba variety.

Yes, tourmaline can be used for an engagement ring, but it requires care. With a hardness of 7 to 7.5 on the Mohs scale, it is durable enough for everyday wear but can still be scratched or damaged over time. If used in an engagement ring, a setting that protects the gemstone should be considered.

A tourmaline’s value is based on its colour, clarity, size, and origin. The most valuable tourmalines are those with vivid, highly saturated colours. Paraiba tourmalines, known for their striking neon blue-green colour, are among the most expensive. Stones with good transparency and few inclusions command the highest prices.

Some tourmalines are heat-treated to improve their colour by removing brownish or greyish tones. Some pink and red tourmalines are also irradiated to enhance their vibrancy. These treatments are common and generally accepted in the gemstone market.

The rarest tourmaline is Paraiba tourmaline, a neon blue-green variety found in Brazil and later in Nigeria and Mozambique. Its intense colour comes from traces of copper, making it unlike any other gemstone. Due to its rarity and demand, Paraiba tourmalines can be extremely expensive, exceeding the prices of sapphires, rubies and emeralds.

Tourmaline is the birthstone for October, along with opal. Because it comes in so many colours, it offers a variety of choices for those born in this month.

Tourmaline is believed to promote balance, protection, and emotional healing. Different colours are associated with different meanings. Pink tourmaline is linked to love and compassion, while green tourmaline represents growth and renewal. Historically, it has been considered a stone of creativity and confidence.

Natural tourmalines often have small inclusions, while synthetic tourmalines are rare but can be created in a lab. Some imitations, like glass or synthetic spinel, may be sold as tourmaline, so it is best to buy from reputable sources. A professional gemologist can verify authenticity through testing.