Including the subtle style, there are many factors of 18th century gem settings that can enlighten a gem collection. These factors are usually not known to the novice collector of period jewelry.
Early 1700 broaches and sprays employed a solid back setting and the stones were not visible from this position.
After 1760, the open and the underside of the gems began to show through. Nearly all of the 1,700 diamonds were rose cuttings.
This style of cutting was considered by some diamond admirers as a way to hide inferior quality. The term “brilliant” did not imply a certain quality, but instead refers to the cutting style.
The rose diamond has a flat back, a sharp pointed apex, with triangular facets numbering altogether 12, 24 or, in rare cases, 36.
The more recent double-cut brilliant can be described as two cones attached at their base. The top one is cut flat, has an eight-sided face (called a “table”). The base is cut to form a smaller face known as a “culet.”
Rose cutting began in the Dutch lapidaries around 1643. At the beginning of the 1600s, Venetian Vincengo Peruzzi developed the brilliant style.
Before that era, the normal cutting was to cut the stone flat, or in the shape of a four-sided pyramid. A rose-cutting appears more attractive than a brilliant cut.
Throughout the 1700′s, silver and gold were used in settings, and platinum was rarely utilized except as a medium for snuff boxes.
After the accession of King George III, the open setting was used worldwide, except when adorned stones were mounted. These were still solid backed, but painted with India ink on the stones back.
There is not much distinction between French and English craftsmanship. A large amount of jewelry traditions were shared by both countries.
Another note on 1700 jewelry – it followed mainly the prevailing rococo patterns and never degenerated in the formlessness of that finicky generation’s fashion.
Rarely can an unaltered piece of 1700 jewelry be located, as generations of ownership have often used new settings.