The Palm Tree Brooch
Christie’s Auction, Dec. 6
Gary Roskin –
Roskin Gem News Report –
December 07, 2022 –
The Palm Tree Brooch, a Cartier estate piece, was purchased at auction last evening for $1,008,000, $300,000 over the auction estimate. It is a magnificent piece, and one in which you do not appreciate scale until it is worn. (see images) The center stone is 13 carats!
A “Circular Brilliant?”
The shape of the center diamond is, according to GIA’s diamond grading report, a “circular brilliant.” This is not a common description, but one worth noting.
At first glance, and noting the details on the GIA diamond grading report, the diamond appears to be an older cut, with a small table (47%), fat pavilion mains (lower half facet /lower girdle facet length is less than 50%), and a good sized culet (slightly large).
First thought is that it’s an Old European Cut (OEC). But GIA defines OEC with these criteria:
- Table size: less than or equal to 53 percent
- Crown angle: greater than or equal to 40 degrees
- Lower half facet length: less than or equal to 60 percent
- Culet size: slightly large or larger
With this diamond, the crown angles are too shallow to fit the definition. This diamond is transitioning to the modern round brilliant, or what we would have called simply “a transitional cut.” On a diamond grading report, the words “transitional cut” tells the reader what is happening, but it doesn’t actually tell us the shape of the diamond. So, the transitional cut, the step between Old European and Modern Round Brilliant, is called “Circular Brilliant.” GIA’s definitions for the Old Mine Cut, Old European Cut, Circular Brilliant, and Modern Round Brilliant, can be found here: Describing 58-facet Round Brilliant-Cut Diamonds at GIA