Platinum processing has numerous inherent differences when compared to conventional gold and silver alloy handling procedures.  In general, high temperatures dominate the process of platinum.  Significant points can be separated:

• Melting operations require special crucibles, heat sources, molds and temperature measurement equipment.  Contamination risks during melting require special attention.  Solidification shrinkage losses from pouring even a large ingot can be significant.
   
• The process of assay sample preparation requires attention to detail and methods slightly different from conventional gold and silver materials.  Determination of platinum is slower than the conventional fire assay, with consideration required of the interference between the platinum group metal elements.
   
• Cold working of platinum by most rolling and shaping procedures can progress rapidly, taking advantage of the considerable ductility inherent in most commercial alloys.  Assuming that the grain size of an ingot is not too large, overall reductions from 70% to 90% of cross section are possible.  Wire shaping by drawing tension will produce significant wear to steel tooling.  Rolling to shape or utilizing diamond tooling will reduce problems, especially with quality lubricants.  Likewise for stamping operations, clean polished tooling with correct lubrication and frequent sharpening will control excessive wear caused by platinum.
   
• Annealing operations require attention to cleanliness with different equipment and ceramics required to attain the 1200oC to 1400oC range and prevent contamination.
   
• Seamless tube manufacturing can be difficult when platinum bonds to tooling.  Mandrel drawing on steel or copper can minimize some of the problems that quality lubrication cannot.  More study is required in this area.
   
• Contamination of platinum can be avoided with good housekeeping, with special attention to detail during high temperature processes such as melting, annealing and welding.

Overall, platinum has properties of color, high density, resistance to corrosion and stiffness that are unique among precious metals.  Obstacles encountered in processing platinum can be surmounted with care and attention to detail.  Numerous areas of platinum manufacturing require more study to overcome or minimize the inherent properties that conflict with high productivity processing methods.

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Platinum Fabrication Processes
Greg Normandeau
Imperial Smelting & Refining Co

This is an abbreviated version of the original work. For full technical details, please consult the original paper.