Abstract: An external part of a timepiece has a substrate that includes a base layer and a surface layer, the surface layer including Ti or stainless steel; and a coating disposed on the substrate. The coating includes an outermost layer formed primarily of TiC defining an external surface, and an interior layer formed primarily of TiC positioned between the substrate and the outermost layer. An elastic modulus of the interior layer is greater than the elasticmodulus of the outermost layer.

Abstract: A watch exterior part includes, in order, a substrate made of a metal, a foundation film including any of Ti, TiCN, TiC, TiN, TiO2, Si, and SiO2, and a metal coating mainly including Ru or including a Ru—Ti alloy, the metal coating being configured as an outermost film.

Abstract: An external part of a timepiece has a substrate that includes a base layer and a surface layer, the surface layer including Ti or stainless steel; and a coating disposed on the substrate. The coating includes an outermost layer formed primarily of TiC defining an external surface, and an interior layer formed primarily of TiC positioned between the substrate and the outermost layer. An elastic modulus of the interior layer is greater than the elasticmodulus of the outermost layer.

Abstract: A decorative article has a substrate of which at least part of the surface is configured with Ti or stainless steel; and a coating made of primarily TiC and disposed on the substrate. The coating has at least a first region, and a second region disposed closer to the substrate than the first region. The elastic modulus of the second region is greater than the elastic modulus of the first region.

Abstract: A timepiece part includes: a substrate; and a first coating configured from a material containing cobalt as a primary component, and 26 mass % to 30 mass % of Cr, and 5 mass % to 7 mass % of Mo. The first coating has an average signal intensity of oxygen of 0 counts/sec to 150 counts/sec as measured by SIMS relative to a 1.0 ?m-thick reference film of a composition containing Co: 62.8 mass %, Cr: 28.2 mass %, Mo: 6.0 mass %, C: 1.5 mass %, and Ar: 1.5 mass %.

Abstract: A timepiece part according to the invention includes: a substrate; and a first coating configured from a material containing cobalt as a primary component, and 26 mass % to 30 mass % of Cr, and 5 mass % to 7 mass % of Mo. The first coating has a surface with a percentage surface area increase of 0% to 1.2% as measured by atomic force microscopy against a reference flat surface.

Abstract: A timepiece part has a substrate; and a first coating made from a material containing Co and including greater than or equal to 26 wt % and less than or equal to 30 wt % Cr, and greater than or equal to 5 wt % and less than or equal to 7 wt % Mo. The substrate is preferably made from a material including at least one of stainless steel and Ti. A second coating made of a material including at least one of TiC and TiCN is preferably disposed between the substrate and first coating.

Abstract: A decorative article has a substrate of which at least part of the surface is configured with Ti or stainless steel; and a coating made of primarily TiC and disposed on the substrate. The coating has at least a first region, and a second region disposed closer to the substrate than the first region. The elastic modulus of the second region is greater than the elastic modulus of the first region.

Abstract: A decorative article comprises a substrate being primarily composed of at least any of Ti and stainless steel in at least part of a surface vicinity thereof; a first coat being formed on the substrate and being primarily composed of TiCN; a second coat being formed on a side of the first coat opposite a side facing the substrate and being composed of stainless steel; wherein a combined C content ratio and N content ratio in the first coat is equal to or more than 2.0 wt % and less than or equal to 19 wt %.

Abstract: A decorative article comprises a substrate being primarily composed of at least any of Ti and stainless steel in at least part of a surface vicinity thereof; a first coat being formed on the substrate and being primarily composed of TiCN; a second coat being formed on a side of the first coat opposite a side facing the substrate and being composed of stainless steel; wherein a combined C content ratio and N content ratio in the first coat is equal to or more than 2.0 wt % and less than or equal to 19 wt %.

Abstract: A method of manufacturing a decorative article, including a first coating formation step of forming a first coating of primarily TiN on a substrate; a second coating formation step of forming a second coating on the first coating by means of a dry plating method using a target containing 70.0 wt %?85.0 wt % Au and 15.0 wt %?30.0 wt % Cu; a heat treatment step of promoting formation of a solid solution of the constituents of the second coating by applying a heating process that heats the substrate on which the first coating and the second coating are disposed to 300° C.?395° C. and then applying a cooling process; and an acid treatment step that, of the constituents of the second coating to which the heating process was applied, removes the constituents not forming a solid solution by applying an acid treatment.

Abstract: A method of manufacturing a decorative article, including a first coating formation step of forming a first coating of primarily TiN on a substrate; a second coating formation step of forming a second coating on the first coating by means of a dry plating method using a target containing 70.0 wt %?85.0 wt % Au and 15.0 wt %?30.0 wt % Cu; a heat treatment step of promoting formation of a solid solution of the constituents of the second coating by applying a heating process that heats the substrate on which the first coating and the second coating are disposed to 300° C.?395° C. and then applying a cooling process; and an acid treatment step that, of the constituents of the second coating to which the heating process was applied, removes the constituents not forming a solid solution by applying an acid treatment.

Abstract: A decorative article with a whitish gold color that can retain an exceptionally beautiful appearance over a long period of time, a surface processing method manufacturing such decorative articles, and a timepiece having such decorative parts. The surface processing method includes forming a primary coat on at least part of a surface of base material, and forming a film composed of an Au—Pd—Fe—In alloy containing about 0.1 to about 10 wt % Pd, about 0.1 to about 8 wt % Fe, and about 0.1 to about 10.0 wt % In using a dry plating method. The primary coat preferably is, or includes, a buffer layer for buffering the potential difference between the base material and the film. The film is preferably formed in a dry plating method using multiple targets of different metal compositions.