A piece of jewellery, wherein the jewellery comprises at least one tag or chip programmed with at least a unique identification code, and a tag reader is configured to read the tag or chip when the tag reader and the piece of jewellery touch, or come into close contact and, display a message or content associated with the unique identification code.

A piece of jewellery, wherein the jewellery comprises at least one tag or chip programmed with at least a unique identification code, and a tag reader is configured to read the tag or chip when the tag reader and the piece of jewellery touch, or come into close contact and, display a message or content associated with the unique identification code.

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.

An external part element or component for a timepiece or piece of jewellery made with a fibre-reinforced polymer matrix composite material, this external part element including on at least one of the faces thereof at least one cavity wherein an insert made of metallic glass is housed. A method for manufacturing such an external part element is also described.

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 m, 2 to 10% of Fe3O4 in grain size of 3-50 m, 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.

Methods of temporarily enhancing the luster and/or brilliance of a piece of jewelry, a gem stone, or a piece of jewelry including a gem stone including applying a non-aqueous composition to the piece of jewelry, the gem stone, or the piece of jewelry including a gem stone.