The Secret Colours of Tanzanite: Discover what makes unheated tanzanite so special
Go ahead and picture a tanzanite. You’re likely envisioning a stunning royal blue or violet stone. You’re totally correct, this vibrant hue is what most of the tanzanite jewellery on the market is known for.
What you may not know is that this colour is almost always the result of a heating process to alter the colour of the stone. Now, something truly special, is unheated tanzanite, which reveals a remarkable secret hidden within the stone.
The scientific phenomenon that makes tanzanite so special is called pleochroism. The name means "many colours," and it refers to the ability of a gemstone to appear in different colours when viewed from different angles.
Many gemstones are dichroic, meaning they show two colours as you tilt them. A skilled gem cutter must choose the orientation of the stone carefully to best showcase these colours. But tanzanite is in a rare category all its own: it is a trichroic gem, capable of showing three distinct colours at once.
The Unheated Tanzanite Experience
In its natural, unheated state, a tanzanite crystal can be a mix of hues, often appearing in shades of brown or burgundy alongside its inherent blue and violet. When the stone is viewed from different angles, you can see all three of its colours at once. It is a stunning display of natural complexity.
For the commercial market, this trichroic nature is typically simplified through a mild heating process. Heating the rough stone permanently removes the brown and burgundy colours, leaving behind the concentrated, brilliant blue and violet tones that are so highly prized in tanzanite rings and other fine jewellery. While this process enhances the gem's beauty and is widely accepted in the industry, it removes or minimises the very quality that makes natural tanzanite so unique.
A Rare Glimpse into a Gem's True Nature
Because the majority of tanzanite is heated, finding a truly unheated piece with good colour saturation is a real treat for those that love untreated gemstones. These gems offer a fascinating glimpse into the stone’s true, unadulterated form. The subtle interplay of colours in an unheated tanzanite reveals a deeper character and natural beauty that is a testament to its singular nature.
So, the next time you see a beautiful tanzanite, remember the science behind it. And if you also believe the qualities of untreated stones to be mesmerising, you’re in the right place, as I love to create pieces with it! Contact us to commission a piece today.
