A final layer of a multi-layer of thin deposit and lacquer layers of a decorative faceted functional stone formed by 10 to 35% of nano/colloidal silica, optionally nano/colloidal alumina, 30 to 50% of encapsulated aluminium flakes in grain size of 15-80 μm, 2 to 10% of Fe3O4 in grain size of 3-50 μm, and 10 to 40% of polyisocyanate-hardened mixture of epoxy and polyether resin, and a method for increasing the opacity and hardness of a multi-layer of thin deposit and lacquer layers of a decorative faceted functional stone by applying this final layer.

Provided is a gemstone treated with a cut expressing a reflected image pattern not recognized before, wherein the gemstone includes the crown 100 having the table 110 and plural bezel facets 130, and the pavilion 200 having the culet 210 and plural main facets 220; the girdle 300 is formed between the crown 100 and the pavilion 200; a direction of a horizontal component of an inclination direction of the bezel facet 130 from the table 110 to the girdle 300 is set to be different from a direction of a horizontal component of an inclination direction of the main facet 220 from the culet 210 to the girdle 300; and inclination angles of the bezel facet 130 and the main facet 220 are set so that a light that enters the table 110 is reflected by two of the main facets 220 and emitted from the bezel facet 130.

A gemstone includes a crown, a pavilion, and a girdle disposed between the crown and the pavilion. The surface of the gemstone is generally divided into a number of groups of interlocking facets disposed at a variety of angles. The groups of facets comprising the surface of the crown generally include star facets, upper main crown facets, upper intermediate crown facets, lower main crown facets, lower intermediate crown facets, and upper girdle facets. The upper girdle facets generally abut an upper edge of the girdle. The groups of facets comprising the surface of the pavilion include culet-adjacent facets, lower candle facets, lower main pavilion facets, upper candle facets, upper main pavilion facets, and lower girdle facets. The lower girdle facets generally abut a lower edge of the girdle.

The invention relates to a diamond-based gem. The diamond-based gem may include, at least one first portion comprising one of: a single crystal diamond and a transparent polycrystal diamond; and at least one second portion comprising opaque polycrystal diamond. Further are disclosed several methods for manufacturing such a diamond-based gem.

A sparkling, oblong-shaped precious stone, such as an emerald or cushion cut diamond is formed by a planar table facet, a girdle, two pairs of long crown facets located between the table facet and the girdle, and the two pairs of long pavilion facets located between the base of the stone and the girdle.

A size enhancing jewelry setting for a precious stone includes a setting body with a holding portion that is configured to engage and hold the precious stone affixed to the setting body. A faceted plate is supported by the setting body. The faceted plate has a central opening for the passage of a pavilion region of the precious stone therethrough, an upward facing reflecting surface that partially extends below a girdle of the precious stone and which faces a portion of the pavilion region of the precious stone in spaced relationship thereto, and a portion that protrudes peripherally beyond the girdle of the precious stone. The faceted plate is being configured to reflect light that emanates from the pavilion of the precious stone outwardly and upwardly, the reflected light surrounding and extending beyond the precious stone to produce a visual effect of the precious stone being larger in a peripheral dimension thereof than it actually is.

Embodiments of the disclosure provide a gemstone, jewelry piece, and method for faceting a gemstone. The gemstone, includes: a top portion having a spheroidal surface, the spheroidal surface acting as a refractive surface for light incident on the top portion of the gemstone and focal point lens originator; and a bottom portion shaped as a cone, the cone acting as a light axis to form a focal point on a reflective surface at a base of the gemstone.

A method for producing a gemstone, in particular a diamond, in the shape of a star with several arms, the method including taking a basic, brilliant cut gemstone, the gemstone including a basic crown, a basic pavilion and a basic girdle joining the basic crown and the basic pavilion and defining a plane, cutting a plurality of facets in the respectively basic crown, pavilion and girdle, to obtain a transformed gemstone delimited by a periphery, laser cutting the periphery of the transformed gemstone to produce the star shape.

A size enhancing jewelry setting for a precious stone includes a setting body with a holding portion that is configured to engage and hold the precious stone affixed to the setting body. A faceted plate is supported by the setting body. The faceted plate has a central opening for the passage of a pavilion region of the precious stone therethrough, an upward facing reflecting surface that partially extends below a girdle of the precious stone and which faces a portion of the pavilion region of the precious stone in spaced relationship thereto, and a portion that protrudes peripherally beyond the girdle of the precious stone. The faceted plate is being configured to reflect light that emanates from the pavilion of the precious stone outwardly and upwardly, the reflected light surrounding and extending beyond the precious stone to produce a visual effect of the precious stone being larger in a peripheral dimension thereof than it actually is.

A gemstone including: a table defining a first area; a culet defining a second area with a size equal to a size of the first area; and a scanable indicia positioned in the gemstone between the table and the culet.