A 102-carat flawless diamond is set to be auctioned online by international art, jewelry and collectibles broker Sotheby's. Because of its rarity and estimated value the precious stone is expected to become the most expensive jewel ever sold online.

Appraisers of the 102.39-carat Flawless Oval Diamond have estimated its value to be somewhere between $10 million to $30 million. Only seven flawless white diamonds above 100 carats have ever been sold at auction. The jewel on the auction block early next month is the second-largest oval diamond in the world.

The head of Sotheby's jewelry department in New York, Quig Bruning, said that 100-carat natural diamonds are already extremely rare but ones that are D-color flawless are even rarer. Sotheby's has yet to announce an official starting bid for the diamond but comparable diamonds that have been sold in the past have had bids of more than $15 million.

Sotheby's officially described the size of the stone as being larger than a lollipop. The company is planning to hold a live auction for the stone and several other items Oct. 5 in Hong Kong. Interested bidders can register online this week. If the diamond is sold at more than $6 million, it will become the most expensive piece of jewelry sold online. The record is currently held by a pair of blue and pink diamond earrings, which were sold for $6 million in 2016.

The 102-carat diamond was cut from a 271-carat rough stone that was originally unearthed in the Victor Mine in Canada in 2018. It took experts around 12 months to shape the rough diamond into a Dia-core shape, which Sotheby's says brings out its "brilliance" and "fire."

Similar to gold and other precious metals, diamonds have become a popular form of investment given the international economic downturn. The spread of the coronavirus has caused a shift in investments away from equities to more stable safe-haven assets.

The supply and demand for diamonds and jewelry, in general, were disrupted by the spread of the pandemic, mostly as a result of forced store closures worldwide. Despite this, diamond prices have remained relatively stable.