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Help with Tanzanite grading

Hi there. Recenty I purchased a stone online. Im confused as how to grade the color, as i wanted to know if i overpaid or not. Indoors it looks suprisingly almost too dark but with a nice sparkle, outdoors in indirect light it looks brighter, but doesnt seem to be of top color and saturation as the seller implied. Im not sure how grading is typically done in different lighting situations. Anyways would appreciate your thoughts. I still have some time to return the stone. Fyi paid 1250 usd for this 6 carat stone. The pictures below are taken outdoors in indirect light and the last indoors using iphone.


A very pretty Gem! Color grading can be subjective. I prefer to use adjectives to describe the color as it may be more representative of the gem such as “Gorgeous blue”, etc.

Thanks! I like it too. I didnt really expect to get investment grade tanzanite at that price. Just a little upset the seller cooked up their video and pictures to make it look a lot more saturated. Hopefully i didnt grossly overpay by too much.

I’m just a collector, but have some Tanzanite. This looks like a very nice one…maybe AAA grade. 6 carats for 1250 is, IMV, a good value.

Thanks, that is good to know. Curious what is AAA in relation to the highest and lowest grades? Sorry if this is a simple question.

AA is lighter tone with some lavender, even some gray. AAA is deeper blue with some lavender . AAAA is deep saturated blue. Cannot see lavender in your pics, but you will have to judge that. AAAA is considered investment grade. If you think that is what you have, you have really gotten a good deal for 1250/6cts.

Ok sounds good. Definitely not highest grade since the video of the same stone made by the seller looked much more saturated lol. I also noticed in white fluorescent light the entire stone looks pretty much blue, but in yellow light half of it is purplish. fascinating stone to be sure

I’m a little confused, since you say the seller made the stone look more saturated, but your picture shows a stone that is about as dark as you’d want for dark blue. If the darkness is what you mean by less saturated, then OK, it might be a little darker than optimum, but I don’t really see it that way. The highest grades would have more purple in their blue than what I see. Color grading is hard without the stone in hand, but I would call it a 7 out of 10, and that would give me a jeweler’s memo price of $2700. So I’m thinking that maybe the stone is actually darker in person. However, I’d be surprised if you overpaid at $1250. This is one of those few times when I think that an amateur gem buyer may have actually lucked out. however, as i say, color grading is very subjective, I am not the best at it, and…I’m not sure this is actually tanzanite…you’d need an in person gem ID for that. -royjohn