Largest Diamond Ever Auctioned Expected To Sell For Up To $35 Million

By Diamaris Martino

CHICAGO (CBS) -- Some diamonds aren't meant to be just for rings.

The world's largest flawless white diamond ever auctioned is on the block today in Switzerland.

The 163-carat stone is the centerpiece of an emerald and diamond studded necklace.

The centerpiece is the size of a matchbox, and is set to be auctioned off at Christie's "Magnificent Jewels" sale in Geneva, Switzerland.

Originally it was part of a 404-carat rough stone, that was the largest diamond ever discovered in southwest Africa.

The necklace is expected to be sold for up to $35 million.