The Double Rosette

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

Aware of the very limited supply of large diamonds at acceptable prices and inspired by the success of Single Rosettes, cutters experimented with various combinations of small rough in an attempt to create attractive alternatives. Some of these turned out to be truly impressive. The four-petalled Rosette had already appeared by 1411 and the Single Rosettes with five to nine components some thirty years later. Finally, in about 1480, the ingenious Double Rosette made its appearance. Combining two completely different cuts in one design was an original and daring idea, and the result was incomparably beautiful. The fashioning of these cuts called not only for the greatest precision but also for a very large stock of rough from which to select the appropriate cleavages. It is possible that these Double Rosettes were the work of one single craftsman, or a small group of collaborators. The settings, it seems, were all produced by casting, another indication of a degree of specialization unusual at that time.

The new design comprised anything from ten to eighteen diamonds of two different shapes: the fan-shape, familiar from the Single Rosette, and the lozenge, which had the outline of an equilateral parallelogram. The lozenge cut, which was developed specifically for the Double Rosette, is quite intricate. It has two sloping main facets in the crown, similar to a Hogback. These meet at an angle of approximately 100° and are separated by a ridge shaped like a arrow, tapering facet, sharply pointed at the outer end of the stone and broad enough at the inner end to allow a pin to fix it in the center of the jewel.

The Double Rosette, even though it may appear to be quite flat, produces a distinctly three-dimensional effect which gives fascinating fire and brilliance. Earlier, such light effects had been arrived at by chance as, for instance, when ideal height proportions were discovered in Burgundian Point Cuts. It is possible that large, richly faceted Burgundian diamonds, with their almost circular outlines, were the models for which the new Rosettes were intended as a popular substitute. Calculations show that the display of a Double Rosette with sixteen components weighing about 3ct matches that of a Burgundian Point Cut of approximately 16ct—which would have to have been cut from a rough weighing at least 20-25ct! To make the Rosette it would suffice to have sixteen small cleavages weighing less than half a carat each.

I have investigated the effects of different kinds of light on a well-fashioned and clean Rosette. When dirty, Rosettes are dull and without luster, but when clean they sparkle brilliantly with all the colors of the rainbow. Candlelight seems to be particularly flattering to them.

The Double Rosette (continued)