My gem cutter said:
This class of Tanzanite belongs to the very top 1% mined and is very rarely seen in the market. Out of a thousand carats mined literally 9 or 10 will be of this grade. These colours are extremely rare and their rarity makes them attractive to investors.
Sparkling with brilliance and life and imbued with a crisp, scintillating blue, this gorgeous 2.60 carat trillion is exceptional. Its colour is unsurpassed - an extremely intense saturation, cut on the blue axis. Flawless. Truly beautiful and very rare.