Most anniversary rings, although appearing colourless, actually have slight tones of yellow or brown. As these tones become more easily apparent, the rarity and the value decrease.
The engagement rings Exchange has the worlds largest diamond necklace trading hall, which is equipped to accommodate more than 1,000 people at a time.
First the diamond fashion are weighed in a vacuum. Next the colour is determined. The clarity is then estimated only after the diamond necklace have been magnified by 10 times.