Chìyàn 赤焰 (Crimson Flame)

This is not regular leather. Shell cordovan comes from a thin sheet of fibrous tissue called the "shell," found under the rump of a horse. Each horse only yields two small shells. 

Rocado in Tuscany tans theirs for six months in pits using natural vegetable tannage. The marbled red finish is achieved by shaving the outermost layer of the shell to expose the leather's own veins and fibres, then dyeing it with aniline. No two pieces look the same. The pattern on this collar is yours alone.

The interior is lined with Bisanzio Oro, a full-grain vegetable-tanned leather from Conceria Puccini Attilio in Ponte a Egola. Bisanzio gets its rustic metallic look from a hand-stained aniline process that shifts colour as the light hits it. It's drum-dyed, fattened with natural oils, firm but pliable against the neck. The keeper is cut from the same hide so the gold runs continuously around the collar.

The stitching is Lajin Twist gold metallic thread, saddle stitched by hand with two needles through every single hole. Each stitch is structurally independent, so if one breaks, the seam still holds. This is the same technique Hermès uses on their bags. It takes around ten times longer than machine stitching but it's the only way to get a seam that outlasts the leather.

Hardware is 24K gold PVD on 316L surgical-grade stainless steel from Hility. PVD bonds the gold to the steel at a molecular level, so it doesn't flake, peel or wear off. It scores 800 to 4,000 HV on hardness against 100 to 200 for regular gold plating. The same hardware specification is used by luxury watch and bag houses.

The edges are burnished through 10 stages using Tokonole, a Japanese water-based burnishing gum made from natural paste, resin and wax. Each stage is polished by hand with canvas and friction until the edge is sealed glass-smooth. You cannot do this at scale. It is slow, manual saddlery work and it is what separates real leather goods from production leather goods.