The Four- Petalled Diamond Rosette

(via Diamond Cuts in Historic Jewelry:1381-1910) Herbert Tillander writes:

The earliest type of Rosette was a very simple combination of stones intended to give the impression of a large, pointed diamond. It was composed of four Shield Cut fan-shaped diamonds placed close together like a four-leaf clover and held in place by small prongs. The four triangular facets, with their pointed ends meeting in the center, might well be mistaken for the four main facets of a single, low, Point Cut diamond. These Rosettes are almost impossible to identify in portraits—in most cases the painters have confused them with low Pyramid Cuts.

Detailed analysis of components of Rosettes of this kind show that the cut, though in fact fashioned from any flat irregular rough, was originally inspired by a ‘was’ type of cleavage. Loss of weight, even from perfectly developed ‘wases’, seems to have been at least 50 per cent, but neither this fact nor the long hours of precise fashioning involved appear to have bothered the cutters, for the resulting ‘flowers’ were soon in great demand. Each of the four fan-shaped diamonds was fashioned as follows: the crown was given one semi-circular and one triangular facet, usually separated by a very narrow facet, or even by a ridge. The result was an impressive mirroring square enclosed inside an attractive narrow border. In the pavilion, the triangular culet was enclosed by a semi-circular facet with truncated corners at the broad end, and on either side by rhomboid facets meeting at the point.

There is evidence from an inventory of John the Fearless, Duke of Burgundy, that four-petalled Rosettes existed as early as 1411. Another inventory mentions that in 1414 Jean, Duke of Berry, received from the Paris jeweler, Constantin de Nicolas, a ring with ‘une flour de diamant’. It is possible that Rosettes may even have originated from Paris.