Optically transparent mark for marking gemstones

The invention relates to marks used for marking gemstones, inter alia rough or cut diamonds, containing various types of information such as, for example, an identification code, and more particularly relates to marks which are invisible to the naked eye and under magnifying glasses and various types of microscopes, and which are placed inside the body of a rough or cut diamond without producing an effect that is detrimental to the quality of said rough or cut diamond. The invention addresses the technical problem of extending the use of such a mark to rough diamonds containing different amounts and types of natural impurities, inter alia nitrogen, and achieves the technical result of solving said problem while at the same time simplifying the marking process and reducing the potential effect of said process on the properties of the stone. This technical result is achieved by the use of an optically transparent mark placed inside the body of a rough or cut diamond, said mark containing predetermined encoded information and consisting of a given combination of micron- or submicron-sized optically transparent elements that are regions containing an elevated concentration of atomic defects in the crystal lattice of a rough or cut diamond, said atomic defects in the crystal lattice of a rough or cut diamond being vacancies and interstitials, wherein information is encoded in at least two regions of elevated concentration of said atomic defects.