Yes, it is worth buying. Like a diamond, the value of tanzanite is dependent on the four c's. Richer hues are more valuable. The majority of tanzanites are relatively clean, and obvious inclusions have a significant impact on their value. At 1 carat, 2 carats, and 3 carats, the price per carat increases. The price per carat reaches its maximum at 3.00 carats and is very stable up to 20 carats. Prices might vary by up to 50% depending on the cut and polish quality.