PATEK PHILIPPE. A RARE AND FINE YELLOW GOLD WORLD TIME WRISTWATCH WITH CLOISONNÉ ENAMEL DIAL, IN SINGLE FACTORY SEALModel/Reference: World Time/5131JMovement No: 5'618'823Case No: 4'557'027Year: 2012Calibre: 240 HU, automaticDial: Cloisonné enamel dial, signed on bezelCase: 38mm, 18k yellow gold, transparent case back, signedStrap: Endangered species, 18k yellow gold Patek Philippe deployant claspAccompaniments: Patek Philippe box, certificate and instruction manual.注脚百達翡麗，「World Time」5131J型號，精緻罕見黃金世界時間自動上弦腕錶，配掐絲琺瑯錶盤，原廠未開封(單封)，年份2012。附原廠錶盒、證書及說明書。Exemplary of Patek Philippe's rare handcrafted series, the present lot Reference 5131J depicts the famous enameled world map. Very thin gold wires (0.1mm) were used to separate the enamel colours, as one may notice the shimmery sparkles outlining the continents giving depth and dimension to the painting. Utilizing various shades of blue for the oceans, as well as shades greens and browns for the lands to create this superb dial. This showcases the highest level of skills and craftsmanship, typified by Patek Philippe.Cloisonné enamelling is an ancient decorative technique that involves the laying of gold wires in intricate designs with the negative spaces filled with enamel. Enamel is a vitreous substance based on silica sand, coloured by adding metal oxides. The enamel is crushed to a fine powder and mixed with water to make a paste. According to Patek Philippe, after application and once dry, this paste is fired in a kiln at temperatures exceeding 800°C, fusing to the metal base of the dial and becoming extremely hard and stable. Depending on the intricacy of the design, a model can return to the kiln up to 12 times.Due to the complexity of the process and the skills required to craft such a dial, this timepiece is very limited and unique. Reference 5131J in single factory seal is highly sought-after by discerning connoisseurs with an appreciation for this artistry.