Method for controlling the polishing of gemstones

A method for controlling the polishing of a gemstone, said method comprising:

• a. obtaining a three-dimensional model of the gemstone;
• b. fixing the gemstone in a dop of a tang of a polishing device, wherein an initial facet to be polished is aligned in the dop;
• c. obtaining of at least one image of the initial facet to be polished while the gemstone is in the tang, such that a contour of the initial facet can be determined from the at least one image;
• d. based on the obtained at least one image and the obtained three-dimensional model, determining at least first dop setting parameters for a first planned facet positioned between the initial facet to be polished and a desired final polished facet;
• e. based on the first dop setting parameters for the first planned facet, setting the dop for obtaining a polished gemstone having a polished facet approaching the first planned facet;
• and polishing the gemstone accordingly;
• f. obtaining of at least one image of the polished facet while the gemstone is in the tang, such that a contour of the polished facet can be determined from said at least one image;
• g. based on the obtained at least one image of the polished facet and the three-dimensional model, determining at least further dop setting parameters for a further planned facet;
• h. based on the further dop setting parameters for the further planned facet, setting the dop for obtaining a polished gemstone having a polished facet approaching the further planned facet;
• and polishing the gemstone accordingly;
• i. if necessary, repeating the steps f-h until the desired final polished facet of the gemstone is obtained;
• wherein the gemstone remains fixed in the dop during steps (c)-(i).