A Jeweller’s Guide to Tourmaline: Identification Tips and Jewellery Making Advice
Welcome to the colourful world of tourmaline!
Renowned for its striking range of colours, tourmaline is one of the most diverse gemstones you can work with. Whether it’s a vivid green, rich pink, deep blue, or even bi-coloured, tourmaline offers endless possibilities for jewellery design.
Let’s explore what you need to know about tourmaline and how to work with this stunning stone.
Basic Identification Information
Name & Synonyms:
Tourmaline.
There are lots of different trade names for gemstones that are part of the tourmaline family, I’ve listed them below with a short description.
Species:
Complex borosilicate mineral group
Colour Range:
Purple, Red, Orange, Yellow, Green, Pink, Blue, Colourless, Black, Brown.
(almost any colour is possible with tourmaline)
Refractive Index:
1.624 – 1.644 (-0.009, +0.011)
Birefringence:
0.013 – 0.040
Optical Sign:
Uniaxial negative
Pleochroism:
Strong, with two distinct colours visible depending on the angle of view.
Specific Gravity:
3.00 – 3.26
Fluorescence:
Usually none to weak
Lustre:
Vitreous
Clarity:
Can be type 1, 2 or 3 depending on specific type.
(Type 1 is usually eye clean, type 2 usually included, type 3 nearly always included)
Gems Often Mistaken for Tourmaline:
Spinel, garnet, ruby, topaz
Mohs Hardness:
7 to 7.5
Wearability:
Good. Tourmaline is suitable for most jewellery types, including rings, pendants, and earrings. While it’s durable, it should still be protected from hard knocks or scratches from harder stones.
Birthstone:
October (along with opal)
Common Treatments
Many tourmalines undergo heat treatment to enhance their colour, particularly for lighter or brownish stones that are transformed into more vivid greens, blues, or pinks. This treatment is stable and generally not considered problematic.
Durability Considerations
Tourmaline is relatively durable but can be susceptible to chipping or breaking when exposed to sharp blows.
It’s generally considered to have good wearability, but, because of its cleavage in certain directions, tourmaline should be set with care to avoid damage.
For high-traffic jewellery, such as rings and bracelets, a bezel or halo setting is ideal, while prong settings work well for pendants or earrings.
Jeweller’s Setting Tips
When setting tourmaline, consider its potential for inclusions and colour zoning. The stone’s unique appearance can be enhanced by aligning it with the most striking colours in the stone.
For rings, it’s best to use a setting that offers protection, such as a bezel or low-profile setting, to reduce the risk of chipping.
Tourmaline is also sensitive to extreme heat, so avoid soldering near the stone or exposing it to direct flames. Use a heat sink if adjustments are necessary after setting.
Care Instructions
Cleaning:
Use warm, soapy water and a soft cloth or brush to clean tourmaline. Ultrasonic and steam cleaning should be avoided, as the stone may have inclusions that can be damaged by these methods.
Storage:
Tourmaline should be stored separately from harder stones like diamonds or sapphires to avoid scratches. A soft cloth pouch or a jewellery box with individual compartments works best.
Daily Wear:
Tourmaline is suitable for daily wear in most jewellery types, but caution is advised for rings, especially those worn on active hands.
Aesthetic & Design Insights
Tourmaline’s diverse colour range allows it to be used in virtually any jewellery style, from vibrant statement pieces to subtle accents. The most popular colours, including green, pink, and blue, lend themselves well to both contemporary and traditional designs.
Metal Pairings:
White gold and platinum highlight cooler tones like blue and green tourmaline, lending an elegant, modern feel.
Yellow or rose gold enhances warmer hues like pink and red, giving the piece a rich, luxurious look.
Companion Stones:
Diamonds complement tourmaline beautifully, offering a bright contrast to the gemstone’s colour.
Sapphires, moonstone, and quartz are also great companions, especially for designs aiming for a softer or more harmonious look.
Design Styles:
Tourmaline shines in both minimalist settings, where the stone takes centre stage, and more intricate, vintage-inspired designs, where its colour diversity can add depth and interest.
Market & Ethical Notes
Tourmaline is mined in various locations worldwide, including Brazil, Africa, and Afghanistan.
The mining of Paraiba tourmaline, in particular, has raised concerns over ethical practices due to the gem’s rarity and high demand.
As with all gemstones, sourcing from reputable suppliers who prioritise fair trade and sustainable practices is crucial.
Symbolic & Spiritual Meanings
Tourmaline is often associated with protection, healing, and balance.
Different colours of tourmaline are believed to have various metaphysical properties, such as promoting emotional healing, supporting physical vitality, or enhancing spiritual awareness. Green tourmaline, for example, is said to align with the heart chakra, while pink tourmaline is connected with love and compassion.
It’s also known as a stone that can be used to dispel negative energy, making it popular in spiritual practices, such as meditation or energy healing.
Etymology
The name "tourmaline" is derived from the Sinhalese word "toramalli," meaning "stone with mixed colours," a fitting description given its wide range of hues.
Varieties and trade names
Achroite - colourless
Canary Tourmaline - bright yellow
Cat's Eye Tourmaline - a tourmaline stone that displays chatoyancy
Chrome Green Tourmaline - a rich, intense green colouring
Indicolite - Blue tourmaline, including purplish Blue and greenish Blue
Paraiba Tourmaline - Green, blue or purple that is so highly saturated it looks neon
Rubelite - Red tourmaline, including orangey Red and purplish Red
Siberite - Purple (a vary rare type of tourmaline)
Veredelite - Green, including bluish Green and yellowish Green
Watermelon Tourmaline - a bi-coloured or tri-coloured variety that is pink and green (sometimes there is also a band of yellow between the green and pink).