A jewelry stone, having a crown, a pavilion and an intermediate part between said crown and said pavilion, referred to as the girdle is disclosed. It has metal fastening means that are designed to allow it to be fastened to said mount, comprising a connecting zone located on said pavilion. The connecting zone is located on a part of or all of a limited-width peripheral sector of said pavilion, in which incident rays on the crown pass into the stone through an air/stone interface, are either reflected by a first pavilion/air interface at a point of the pavilion that is lower than said connecting zone, or are reflected entirely by said first pavilion/air interface of said stone in the peripheral sector having said connecting zone.

Provided is a hard decorative member excellent in scratch resistance. The hard decorative member according to the present invention includes a base and a hard decorative coating film layered on the base, in which the hard decorative coating film includes a gray-tone layer including a compound formed by a reaction of an alloy of Ti and one or two or more metals M2 selected from Nb, Ta, and V with a non-metallic element including at least carbon. It is preferable that the amount of carbon contained in the gray-tone layer is 30 to 70 atm % in a total of Ti, the metal M2, and the non-metallic element of 100 atm %.

A patterned diamond and methods of making such patterned diamond are disclosed. The patterned diamond may include: a single crystal diamond or a polycrystal diamond; and a metallic pattern embedded in the single crystal diamond or the polycrystal diamond such that, the single crystal diamond or the polycrystal diamond encapsulates the metallic pattern from at least 4 sides. The disclosed method may include providing a first portion of a single crystal diamond or a polycrystal diamond; introducing a metallic pattern to at least one surface of the first portion of the single crystal or a first portion of the polycrystal diamond; and growing, using a CVD process or HTHP process, a second portion of the single crystal diamond or the second portion of the polycrystal diamond on the first portion, such that the single crystal diamond or the polycrystal diamond at least partially encapsulates the metallic pattern.

The invention relates to a method for manufacturing a composite component of a timepiece or of a jewelry part, the composite component comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, said method comprising the steps of: providing a porous ceramic preform of the component, providing a metallic material, heating the metallic material to a temperature higher than the melting point of the metallic material, filling the pores of the ceramic preform with the molten metallic material, cooling the metallic material and the ceramic preform to obtain a solidified metallic material in the pores of the ceramic preform, and applying finishing treatments to obtain the composite component, wherein said porous ceramic preform consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SiO.sub.2 and mixtures thereof, and said metallic material is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals. The invention relates also to a composite component of a timepiece or of a jewelry part comprising a porous ceramic part and a metallic material filling the pores of said ceramic part, wherein said porous ceramic part consists essentially of a material selected from the group consisting of Si.sub.3N.sub.4, SO.sub.2 and mixtures thereof, and said metallic material which is selected from the group consisting of gold, platinum, palladium metals and alloys of these metals.

An external part including a substrate and a coating composed of the following successively superimposed layers; an opaque or semi-opaque reflective layer, configured to have a reflectance of at least 90% for wavelengths including between 600 nm and 780 nm, a transparent or semi-transparent layer, having a refractive index to include between 1.45 and 2.8 for a wavelength of 630 nm, an absorbent layer, the layers giving the coating a predetermined interference colour.

Article(s) are disclosed that are formed, at least in part, by a cemented carbide composition having about 8 to about 35 wt. % Co and about 0.8 to about 3.5 wt. % Cr.

The present invention relates generally to jewelry articles comprising a substrate and a metallic, external coating.

A method for decorating a surface of a mechanical part including: taking the mechanical part to be decorated, on which a decoration element is sought to be produced; depositing on the surface a masking layer having a thickness that is at least equal to the thickness of the decoration element to be produced; making, in the masking layer, at least one cavity that coincides with the location on the surface to be decorated, the cavity having a contour that corresponds to the contour of the decoration element and defining a volume; depositing a bonding layer made of an electrically-conductive material on top of the masking layer and on the surface, in the locations of the cavity, to facilitate the bonding of the decoration element; filling the volume delimited by the masking layer and the surface with a filling material in which the decoration element; and removing the masking layer.

A decorative article (100) having an observed colour effect that is changeable depending on observer (200) viewing angle, the article comprising: a decorative element (110) comprising a front side (114) facing a forward direction and a back side (112) opposite the front side facing a rearward direction, wherein the back side comprises a back surface (113) having a first region (122) and a second region (124) surrounding the first region; a first coating (132) arranged on the first region of the back surface, the first coating causing a first colour effect (102); and a second coating (134) arranged on the second region of the back surface, the second coating causing a second colour effect (104) that differs from the first colour effect.