Old English And Old European Cuts

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

In gemological literature, the terms Old English and Old European are used for the same type of round cut. This is confusing,and I should like to suggest that the two names be retained but be given separate definitions: Old English for the fine products of the English master cutters of the eighteenth and nineteenth centuries, and Old European for the poorer-quality diamonds with proportions of all kinds, produced by the major cutting factories elsewhere.

Small and medium-sized Brilliants were, on the whole, haphazardly fashioned. Almost all the exceptions are high-class English jewels. A striking example of a jewel with Old European Cuts is the large Bouquet made in 1760 for the Empress Catherine II, now in the Treasury of the Diamond Fund in Moscow. If such a mixture of different Brilliant Cuts was acceptable to this exacting imperial court, what must not lesser mortals have been satisfied with? Most customers were unfamiliar with the splendor of well-made Brilliants. The emphasis was on the style and execution of the ensemble rather than on the perfection of individual stones. This is why the English cutters were hard put to find customers for their superb—but expensive—products, and eventually went out of production altogether. However, by the late nineteenth century, jewelers were once again realizing that there was a market for well-cut stones and were refusing to buy poor-quality ones, so that Tolkowsky found a great many Brilliants in London as fine in quality as his ‘mathematically calculated’ ideal cut.

For this type of Brilliant cut I should like to suggest the term Early Circular Fine Cut. This would cover the first precision cuts fashioned with mechanical devices and introduced in about 1900, possibly by Morse himself. Crystals could be divided without difficulty by motor-driven circular saws, and the two parts could equally easily be bruted or rounded up into circular outlines on a lathe or cutting machine. The classical high 45° proportions were abandoned; by trial and error, cutters developed modern proportions and an attractive combination of brilliance and fire with the minimum of leakage of light through the pavilion facets.

The table below indicates the limits of variation in the proportions of Early Victorian or Old English round Brilliants.

Table size: 45 – 60%
Crown height: 20%
Crown angles: 36 - 45°
Girdle: very thin
Pavilion depth: 40%
Pavilion angles: c.40°
Culet size: max. 5%

By trial and error the London cutters must have discovered the correct angle for the main facets of the pavilion—an angle which is still applied today. It seems that they retained the old vertical proportions of a crown height equal to half the pavilion depth. However, they continued to try different ways of fashioning the crown, in an attempt to strike a balance between brilliance and fire. There is still no general agreement on the best way to achieve this, but today most Brilliants are fashioned for maximum brilliance and restricted dispersion of color.

Most authors of the nineteenth century, and even some later writers, repeat the definitions given by Jeffries and Mawe. However, one frequently comes across illustrations of incorrect and even impossible proportions. Clearly, the cutters took advantage of the ignorance of most of their customers. They had to compete with low-priced but ill-fashioned diamond of which there were plenty on the market. This is why, sadly, most of the old Brilliants, even the finest, were eventually refashioned.