Optimal Faceting of Colored Gemstones
Fraunhofer ITWM
To achieve an automation of the gemstone production, we have to be able to deal with many different facetings. There is a multitude of basic shapes (pear, emerald, round, rect, trillion, …) and several styles of cuts (portuguese, ceylon, …). In this project we found parametrizations of these facetings and derived algorithms, which yield appropriate values for these parameters. Hereby, “appropriate” means two things: First, as few as possible material of the unmachined part should be lost. Second, a beholder should regard the resulting precious stone as “beautiful”.
An essential challenge is to put the “beauty” into a mathematical form. The shape, the regularity of the faceting and the brilliance, i. e. the way the light is reflected by the stone, are the main factors to be considered. In close cooperation with our partner Paul Wild OHG we succeeded in representing the relevant knowledge of the grinders within our software. From this we get a computer application which is not only able to calculate solutions with maximal volume yield, but also allows the user to select those parameters which depend on taste and fashion like the choice of the shape and the cutting style.
