In addition to the 100-carat emerald, there are two smaller pear-shaped emeralds each weighing 50 carats.

The emeralds are believed to have originated from the same piece of Zambian rough emerald, and have an estimated price of around $4 million. They have not been treated or enhanced.

"Emeralds of this quality and size are rarely seen in public," says Avner Sofiov, the owner of Tzoffey's. "Almost every emerald that is offered for sale in the market, regardless of its size and quality, has been submitted to some degree of processing to enhance it and improve its overall look. This 100-carat piece, extraordinary in size and quality, did not even get an oil bath. It is completely natural."

"This trio will make for a fabulous set - a pendant and earrings," Sofiov added.

The gems, together with hundreds of other, high-quality gemstones and jewelry pieces, will be available for viewing in a special display area next to the trading hall of the Israel Diamond Exchange, from March 17 to 20. Bids are to be submitted in closed envelopes. The exact time of the auction's conclusion and when results will be announced have not yet been decided.

In addition to the Tzoffey's auction, I Hennig/ Fusion Alternatives, and the Rapaport Company will hold two auctions of polished diamonds. These polished auctions are being held in addition to rough diamond tenders organized by I Hennig/Fusion Alternatives and eDiamond.