So you’re considering purchasing a tanzanite engagement ring, and you want to do your homework first before you buy. Smart shopper! In this post, I hope to provide you with everything you need to know about the unique coloring of tanzanite engagement rings, so that you can decide whether buying a tanzanite engagement ring is the right choice for you (and your loved one!).

What Color Is Tanzanite?

You may have heard that tanzanite is a relatively inexpensive alternative to sapphire—which historically was true. Tanzanite Rings HQ explains that it is a relatively new gemstone known for its exquisite shades of blue and purple coloring.

So what color is tanzanite? The official coloring of tanzanite, according to the Gem Identification Book that gemologists reference, tanzanite is a trichroic strong gemstone that displays these colors seen: “blue/purplish or reddish/green or yellow; or blue/lighter blue/purplish or reddish [Note: the presence of green or yellow may indicate natural color.]”

So let’s dissect that statement for all us non-gemologists.

First, the definition of trichroic – this adjective means that a crystal appears with different colors when viewed along the three crystallographic directions. Meaning that in its natural state, tanzanite can exhibit colors of: blue, yellow, and reddish purple.

However, the tanzanite that you see set into engagement rings and jewelry is heat-treated tanzanite, which means that the stone has gone through treatment to transform it from its natural state (where it is often yellowish brown, reddish brown, or greenish yellow) to the popular and well-known intense hues of blue and purple.

So yes, that means the question of “what color is tanzanite” is more complicated than one might think. Natural tanzanite is one color, while heat-treated tanzanite is another. But for the average jewelry purchaser looking to buy a tanzanite engagement ring or tanzanite diamond earrings, the easiest answer to this question is:

Tanzanite is a bluish purple stone. The deeper and more intense the color, the higher quality the stone.

More Tanzanite Info

(The below video shows off some great tanzanite examples)

If you do happen to see greenish or yellow tanzanite, this means that the stone has not gone through heat treatment – and these stones are very rare outside Tanzania, and not worth as much as their treated and polished cousins.

So you’re looking at blue/purple/indigo tanzanite engagement rings and notice that the color even still shifts in the light – that is because under certain lighting conditions, the blue tones of the stone will be more apparent, while under other light conditions, the purple hues will stand out more. This is one of the beautiful, amazing properties of tanzanite, and why a tanzanite engagement ring can be a wonderful choice for someone who wants a timeless, never boring option for an engagement ring.