Diamonds are identified and sold on the basis of the “4c’s”: carat, clarity, colour, and cut. If you’ve ever been into a jewellery store, looked at a fashion magazine, entered the word “diamond” into a search engine, or, of course, visited Dupuis, you’re familiar with these terms, but there are other factors that may influence the demand for, and the value of a diamond.

The shape of a diamond has an important place in its value. The “cut” among the “4Cs” refers to proportion, symmetry, polish, and all the factors that make a diamond bright, lively and beautiful. “Cut” is also the cut style or shape of a diamond. The cut shape may also affect the price.

Round diamonds are the most popular, and are the most costly because so much more of the original square crystal is ground away to make it into a round shape. Other shapes are subject to style and fashion. Pear-shaped diamonds are currently gaining in popularity, and emerald cut diamonds (square or rectangular) are very popular.

For centuries, the most exceptional diamonds were described as being “of the first water”. The finest diamonds were thought to be as pure, clear, and clean as a drop of spring water.

Diamonds are composed of pure carbon, but most diamonds have tiny molecular quantities of nitrogen that causes varying amounts of yellow colour in the gem. These diamonds are called Type I.

Very rarely, a diamond can form with no nitrogen, and it will have no yellow colour. Diamonds that are virtually nitrogen free are called Type II, and if they are Type IIa they can be very pure and colourless.  Type IIa diamonds can be of the rare ”D” and “E” grades. They are also seen as exceptionally clear and transparent gems.

Among the most historically important and desired diamonds in the world are those of Type IIa from the historic source of Golconda, In India, which hasn’t been mined for over 200 years.  Type IIa diamonds do, once in a rare while, occur in other places in the world.

In the current Dupuis Important Jewels Auction we are proud to have the opportunity to offer one of these rare Type IIa diamonds. Not only is it Type IIa, but it is also an impressive 4.24 carats, in a desirable pear shape, of the absolutely colourless grade of “D”, and of the exceptional clarity: VVS2.

LOT 250: A Fine and Rare Diamond and Platinum Ring by Birks (more details)

Whatever you’re looking for in diamonds, the perfect diamond is waiting for your bid.

Lot 414 An Elegant Diamond and
Platinum Necklace, by Graff
Estimate: $180,000-220,000


JUNE 10, 2018


Monday, May 28, 2018 – Saturday, June 2, 2018
Monday, June 4, 2018 – Saturday, June 9, 2018

Daily: 11:00 AM – 6:00 PM (except Sat. until 4:00 PM)
An appointment is not required.

Preview & Auction Details Auction Highlights Online Catalogue View e-Catalogue