Tanzanite has a unique position among all gemstones because it is a pleochroic gem, meaning it displays multidimensional color, making it an exceptionally brilliant possession. When viewed from 3 different crystallographic directions, three different colors can be seen, making tanzanite a ‘trichroic’ material. It can be distinct blue when viewed from one direction and vary from violet to red when viewed from other directions. Tanzanite is the only gemstone that is trichroic in nature.
The dark blue color of tanzanite is beautiful and like no other blue. The most coveted color is a vivid blue surrounded by a delicate hint of purple, which has an indescribable effect in all sizes, but more so in sizes over 10 carats. While larger stones tend to display the more vibrant colors, the smaller stones showcase pastel shades. Tanzanite appears bluer during the daylight, whereas at night, in incandescent light, you can see the red flashes throughout the stone.
Typically, tanzanite color grading is spread into a range of hues from violet blue to blue violet and based on tone and saturation of color. While the deeper colors have greater value, tanzanite with moderate to light colors is still desirable, and sometimes preferred by certain consumers. When you add a fine cut to a rare gem with a remarkable feature of color like tanzanite, it makes a gem of great beauty every time. Below is the definition to the grades you will see on each item we offer.
In the chart below, we show you how tone and saturation work in the context of tanzanite and how GIA grades apply to them. On the vertical axis, you will see the graduation regarding quality. On the horizontal axis, you know the graduation concerning saturation. As tone and saturation increase, the value also increases. The tanzanites on the top row is the deepest and indicates the highest grade, therefore, the highest value.