Method for fabricating timepiece components including a decorative coating of aventurine

Abstract

A method for fabricating a timepiece component partly formed of aventurine, including providing at least one piece of aventurine formed of a mass of coloured glass containing copper crystals scattered throughout the mass; grinding at least one piece of aventurine to obtain a granular powder; depositing at least part of the granular powder on a surface of a support intended to receive a decorative coating; then introducing the support with the granular powder deposited on the surface into a furnace and melting this granular powder so as to obtain, after removing the assembly thus obtained from the furnace and allowing the assembly to cool, an enamel layer made of aventurine which covers the support surface. The timepiece component is, for example, a dial, a moon phase disc or a bezel.

1 . A method for fabricating a timepiece component partly formed of aventurine, comprising the following steps:
 A) providing at least one piece of aventurine formed of a mass of coloured glass containing copper crystals scattered throughout the mass of coloured glass;   B) after step A), grinding said at least one piece of aventurine to obtain a granular powder;   C) making a support from a material having a higher melting temperature than that of said mass of coloured glass, this support having at least one surface intended to receive a decorative coating;   D) after steps B) and C), depositing at least part of said granular powder on said support surface;   E) after step D), introducing the support with the granular powder deposited on said surface into a furnace and melting this granular powder so as to obtain, after removing the assembly thus obtained from the furnace and allowing the assembly to cool, an enamel layer made of aventurine which covers said support surface and forms a decorative coating.   
     
     
         2 . The method for fabricating a timepiece component according to  claim 1 , wherein, between steps B) and D), said at least one part of the granular powder is mixed with a liquid, said step D) consisting in application of said mixture to said support surface. 
     
     
         3 . The method for fabricating a timepiece component according to  claim 2 , wherein a step of drying said mixture deposited on said surface is performed in a drying furnace prior to said step E). 
     
     
         4 . The method for fabricating a timepiece component according to  claim 1 , the sequence of steps D) and E) is repeated several times, so that said decorative coating is formed of a plurality of enamel layers made of aventurine and deposited one on top of the other. 
     
     
         5 . The method for fabricating a timepiece component according to  claim 1 , wherein said granular aventurine powder is formed of grains of aventurine, most of which are of larger dimensions between 50 microns and 200 microns. 
     
     
         6 . The method for fabricating a timepiece component according to  claim 2 , wherein said granular aventurine powder is formed of grains of aventurine, most of which are of larger dimensions between 50 microns and 200 microns. 
     
     
         7 . The method for fabricating a timepiece component according to  claim 4 , wherein said granular aventurine powder is formed of grains of aventurine, most of which are of larger dimensions between 50 microns and 200 microns. 
     
     
         8 . The method for fabricating a timepiece component according to  claim 1 , wherein, after deposition of the enamel layer made of aventurine, a flux is deposited on the enamel layer and is fired to form a transparent upper layer of said decorative coating. 
     
     
         9 . The method for fabricating a timepiece component according to  claim 4 , wherein, after deposition of the plurality of enamel layers made of aventurine, a flux is deposited on the plurality of enamel layer and is fired to form a transparent upper layer of said decorative coating. 
     
     
         10 . The method for fabricating a timepiece component according to  claim 1 , wherein a final step of polishing said decorative coating is performed. 
     
     
         11 . The method for fabricating a timepiece component according to  claim 1 , wherein said support is metal. 
     
     
         12 . The method for fabricating a timepiece component according to  claim 1 , wherein the timepiece component is a part of a watch case, notably a bezel. 
     
     
         13 . The method for fabricating a timepiece component according to  claim 1 , wherein the timepiece component is a part of a watch movement, notably a bridge or an oscillating weight. 
     
     
         14 . The method for fabricating a timepiece component according to  claim 1 , wherein the timepiece component is a display element, notably a dial or a moon phase indicator disc. 
     
     
         15 . The method for fabricating a timepiece component according to  claim 14 , wherein the inner rim and the outer rim form lateral stops for said granular powder deposited on said surface during at least a first sequence of steps D) and E). 
     
     
         16 . The method for fabricating a timepiece component according to  claim 15 , wherein said support has at least one embossed motif inside said surface, said motif forming a lateral stop for said granular powder deposited on said surface during at least said first sequence of steps D) and E), the motif being eventually flush with said decorative coating. 
     
     
         17 . The method for fabricating a timepiece component according to  claim 14 , wherein the timepiece component is a dial which has a convex upper surface, which is at least partially defined by the upper surface of said decorative coating. 
     
     
         18 . The method for fabricating a timepiece component according to  claim 14 , wherein an enamelling process is performed on a surface of said support on the side opposite to that of said surface intended to receive said decorative coating, said enamelling process forming a counter-enamel to conserve the initial shape of said support. 
     
     
         19 . The method for fabricating a timepiece component according to  claim 14 , wherein said decorative coating has a thickness of between 200 and 300 microns.