An ornamental device includes: diamonds disposed on a single support element in a specific physical arrangement, all the diamonds in the specific physical arrangement having a blue fluorescent equal to or stronger than strong blue, wherein all the diamonds in the specific physical arrangement shining clear under a visible light, and shining blue under ultraviolet radiation keeping the specific physical arrangement distinguished from a group of diamonds in the specific physical arrangement, the group of diamonds comprising a mixture of a diamond or diamonds having a blue fluorescence equal to or stronger than strong blue and a diamonds or diamonds not having a blue fluorescent equal to or stronger than strong blue.

Set gemstones, gemstone settings, and methods of setting gemstones including a cut gemstone having a girdle a plurality of horizontal grooves each having an upper edge and a lower edge, wherein the upper edges of the plurality of horizontal grooves are located within the girdle, abut a lower edge of the girdle, or are within 1 millimeter beneath the lower edge of the girdle, and a cylindrical barrel having a central aperture, an open top, a rim at the top forming an upper edge of the barrel, and a plurality of flanges projecting into the central aperture of the barrel located directly beneath the rim, wherein the flanges project into the grooves to maintain the gemstone within the barrel.

Methods, apparatus, and systems for managing optical characteristics of gemstones with diffractive structures are provided. In one aspect, a method includes obtaining a three-dimensional model of a gemstone including representations of surfaces of the gemstone, identifying a region on a surface of the gemstone having an optical value higher than one or more other regions on the surface of the gemstone by analyzing the three-dimensional model of the gemstone, and determining a diffractive structure to be arranged on the identified region of the surface of the gemstone, such that the gemstone with the diffractive structure has a higher optical performance than the gemstone without the diffractive structure. The method can also include fabricating the determined diffractive structure on the identified region of the surface of the gemstone.

A flexible method to provide a variety of value-added coatings to a piece of jewelry or a group of jewelries is disclosed. Atomic Layer Deposition (ALD) and Molecular Layer Deposition (MLD) technique is implemented to deposit a layer of conformal coating on intended jewelry surfaces, including both exterior and interior surfaces, to enhance a vast majority of process-driven or end of use driven properties. The coating compositions include dielectrics material, metals, organic materials or organic-inorganic hybrid materials. The method steps of forming a layer of coating are straightforward and can be tailed to different purposes.

The invention is directed to shallow pavilion, cut diamonds having excellent optical characteristics. The pavilion surface includes a plurality of substantially planar main pavilion facets, each of which extend from the girdle to a pointed culet defining the bottom most portion of the cut diamond. The crown angle is in the range of between about 29 degrees to about 36 degrees, and the pavilion angle is in the range of between about 15 degrees and about 34.5 degrees. The shallow pavilion, cut diamonds of the invention may be either round shaped cut diamonds or fancy shaped cut diamonds.

The invention is directed to shallow pavilion, cut diamonds having excellent optical characteristics. The pavilion surface includes a plurality of substantially planar main pavilion facets, each of which extend from the girdle to a pointed culet defining the bottom most portion of the cut diamond. The crown angle is in the range of between about 29 degrees to about 36 degrees, and the pavilion angle is in the range of between about 15 degrees and about 34.5 degrees. The shallow pavilion, cut diamonds of the invention may be either round shaped cut diamonds or fancy shaped cut diamonds.

A gemstone includes a crown, a pavilion, and a girdle disposed between the crown and the pavilion. The girdle has an octagon-shaped cross-section. 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 intermediate crown facets, lower intermediate crown facets, main 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, candle facets, main pavilion facets, and lower girdle facets. The lower girdle facets generally abut a lower edge of the girdle.

One variation of a diamond composition includes carbon: including a first amount of carbon-13 isotopes and a second amount of carbon-12 isotopes; and sourced from a hydrocarbon mixture including hydrocarbons and formed via methanation of a carbon dioxide mixture. The carbon dioxide mixture: sourced from a sample of air including carbon dioxide and impurities; conveyed through a separation unit configured to remove impurities; including carbon dioxide and impurities; conveyed through a distillation column configured to regulate amounts of carbon-13 isotopes and carbon-12 isotopes; and exhibiting a target ratio of carbon-13 isotopes to carbon-12 isotopes at an outlet of the distillation column. The diamond composition: formed via chemical vapor deposition; and exhibiting an isotopic signature defining a final ratio of the first amount of carbon-13 isotopes to the second amount of carbon-12 isotopes within a first target range corresponding to the target ratio exhibited by the carbon dioxide mixture.

A gemstone includes: a table defining an area; and a scanable indicia formed in the gemstone at least partially positioned within an orthographic projection of the area extending along an axis, the axis extending perpendicularly through the table.

A gemstone includes: a table defining an area; and a scanable indicia formed in the gemstone at least partially positioned within an orthographic projection of the area extending along an axis, the axis extending perpendicularly through the table.