The present disclosure relates to a method of making fancy orange synthetic CVD diamond material. Among other things, the method may involve (i) providing a single crystal diamond material that has been grown by CVD and has a [N.sub.s.sup.0] concentration less than 5 ppm; (ii) irradiating the provided CVD diamond material so as to introduce isolated vacancies V into at least part of the provided CVD diamond material such that the total concentration of isolated vacancies [V.sub.T] in the irradiated diamond material is at least the greater of (a) 0.5 ppm and (b) 50% higher than the [N.sub.s.sup.0] concentration in ppm in the provided diamond material; and (iii) annealing the irradiated diamond material to forming vacancy chains from at least some of the introduced isolated vacancies.

The invention relates to a cut gem comprising a girdle having four girdle sides and four girdle corners, a table realized by a flat facet, a crown which extends between the table and the girdle, in a first direction, and a pavilion which extends in a second direction, opposite to said first direction, between said girdle and a tip of the pavilion. The gem is noteworthy in that the crown has 24 facets, the pavilion has 32 facets and in that the four girdle sides are identical in the form of an arc of a circle, the concavity of which is oriented towards the outside of the gem.

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.

An article of jewelry including a housing that permits passage of a near field communication signal, the housing characterized as having a lower layer joined to an upper layer; a near field communication (NFC) chip housed within the housing; a gemstone covering the upper layer of the housing; and a bezel substantially surrounding the outer perimeter of the housing and on a same plane as the NFC chip, wherein the bezel is formed from a highly electrically conductive material, further wherein the bezel permits near field communication with the NFC chip.

A gemstone includes a crown, a pavilion, and a girdle disposed between the crown and the pavilion. The girdle has a pear-shaped cross-section with a rounded end a tapered end narrower than the rounded end. 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.

Crystals having a modified regular tetrahedron shape are provided. Crystals preferably have four substantially identical triangular faces that define four truncated vertices and six chamfered edges. The six chamfered edges can have an average length of l, and an average width of w, and 8≦l/w≦9.5.

A light-emitting jewelry piece includes a gemstone, a head, and a mounting. The head is configured to interconnect the gemstone to the mounting. The mounting is arranged to secure the light-emitting jewelry piece to a person or a personal adornment.

A light-emitting jewelry piece includes a gemstone, a head, and a mounting. The head is configured to interconnect the gemstone to the mounting. The mounting is arranged to secure the light-emitting jewelry piece to a person or a personal adornment.

There is proposed a decorative element containing (a) a transparent gemstone with a faceted surface comprising convex curved regions, (b) a wavelength-selective layer, and (c) a photovoltaic cell.