Resources

Platinum & Palladium

  • Palladium RU
    • Alloy Composition   95% PD (RU/AG ALLOY)
      Colour   White
      Melting Range   1450 – 1500°C
      Solders   PD E,H, 1020, 18HW
      Specific Gravity   11.7
      Annealing Colour   Cherry Red


      Best used for
      •  Bench Work
      •  Casting
      •  Rolling

      Hints, Tips & Uses
      •  White malleable light-weight metal that is easy to polish
      •  This metal will not cause skin irritation
      •  Do not rhodium plate this metal
      •  If casting metal do not hammer
      •  Casting temperature: 1600°C
      •  Flask temperature: 700-800°C

  • Platinum CU
    • Alloy Composition   95% PT (CU)
      Colour   White
      Melting Range   1740 – 1755°C
      Solders   1020, 1200 & 1400
      Specific Gravity   20
      Annealing Colour   Cherry Red


      Best used for
      •  Bench Work
      •  Casting
      •  Rolling

      Hints, Tips & Uses
      •  General all purpose alloy
      •  Medium to soft alloy

  • Platinum RU
    • Alloy Composition   95% PT (RU)
      Colour   White
      Melting Range   1780 – 1800°C
      Solders   1020, 1200, 1400 & 1600
      Specific Gravity   20.7
      Annealing Colour   Cherry Red


      Best used for
      •  Bench Work
      •  Casting
      •  Rolling

      Hints, Tips & Uses
      •  General all purpose alloy
      •  Universal alloy which can be cast, machined and used for bench

  • Platinum COBALT
    • Alloy Composition   95% PT (CO)
      Colour   White
      Melting Range   1740 – 1755°C
      Solders   1400 & 1600
      Specific Gravity   20.8
      Annealing Colour   Cherry Red


      Best used for
      •  Casting

      Hints, Tips & Uses
      •  High hardness and fine grain
      •  This alloy is magnetic and very hard
      •  Preferred for casting
      •  Used for fine wire & chain making

  • Platinum AU
    • Alloy Composition   95% PT (AU)
      Colour   White
      Melting Range   1740-1755°C
      Solders   1020 & 1200
      Specific Gravity   21.3
      Annealing Colour   Cherry Red


      Best used for
      •  Bench Work
      •  Rolling

      Hints, Tips & Uses
      •  General all purpose alloy
      •  Medium to soft alloy

  • Polishing Platinum
    • •  When polishing platinum, it is important to remove all scratches before the polishing process
      •  When filing, file gently with a diagonal movement. Then repeat with a diagonal movement perpendicular to the first one.
      •  Remove file marks with abrasive paper such as 400, 600 and finer paper
      •  Be sure to use the files and abrasive paper on platinum to avoid contamination
      •  Reduce the surface to at least a 600 grid finish on the bench
      •  Burnish the ring with a polished Tungsten burnisher
      •  Use platinum polishing compound only for luster
      •  Use 2000, 4000 and 8000 grid polishing compounds
      •  When polishing platinum that is joined to gold, be sure the platinum is polished completely before polishing the gold
      •  Check with tool suppliers for brand recommendations


      Things to consider

      •  File gently with a diagonal movement. Then repeat with a diagonal movement perpendicular to the first one, creating a criss-cross pattern
      •  Because gold polishes faster than platinum, it is easy to over-polish the gold portion by trying to polish the platinum and thus ruin the piece.
      •  Hard felt whells and stitched buffs work well on platinum
      •  Burnishing is essential
      •  The polishing process will highlight, rather than remove scratches. They must be removed at the bench

  • Burnishing Platinum
    • Why Burnish?
      Burnishing will work-harden the surface, compress it, close small cavities and make polishing easier. When done properly it reduces rejects from the final polish and saves time. Benefits of burnishing Platinum:
      Burnishing adds extra hardness to the casting, preventing a score of problems such as bending, taking on the shape of the finger, and scratching more easily

      Reference guide to burnishing:
      All platinum casting should be burnished

      How to burnish:
      Using a highly polished tungsten burnisher, rub across the surface of the piece of jewelery. Note, burnishing can also be accomplished using a motor tool

      Tips for better burnishing:

      •  Use a small amount of oil to lubricate the burnisher. This prevents scratching and makes a smoother surface possible
      •  Any scratch on the burnisher will be transferred to the piece. The more polished the burnisher, the better the surface of the piece will be burnished
      •  Use considerable pressure and force. This action will move the surface, compress it and close small porosity holes. The rubbing action hardens the surface, making the final polish much easier.

  • Contamination
    • When contaminated platinum is being stressed through rolling, drawing or hammering, it will crack and become unusable

      Possible causes of contamination during soldering or welding:

      •  Using carbon soldering surface (charcoal)
      •  Abrasive rolled into the Pt surface during fabrication
      •  Filings from other precious or non-precious metals.
      •  Using flux or Fire coat on Pt during high temperature operation
      •  Using steel tweezers near the soldering flame
      •  Oil, grease or soap used during drawing, rolling or general working

      Tips to avoid contamination:

      •  Use only oxidizing flames, avoid redusing flames during soldering or welding
      •  Avoid trapping contaminants in the Pt during cold working
      •  Dedicate files, sanding sticks and bench pins to platinum
      •  Do not weld or solder with acetylene / oxygen flames
      •  Use only Natural gas / Oxygen, Propane / Oxygen of Hydrogen / Oxygen
      •  When using a water torch, disable the flux feature

      Tips on what not to do:

      •  Don’t use Acetylene Gas. Only Natural Gas, Hydrogen or Propane will work with Platinum
      •  Don’t weld without eye protection. UV radiation WILL damage your eyes
      •  Don’t weld when stones are nearby. The welding process will damage most stones
      •  Don’t use your soldering pick or steel tweezers near the flame, as they may contaminate the platinum
      •  Don’t weld on a charcoal block. Platinum and Carbon do not get along.

  • Working with Palladium
  • A guide to Platinum Alloys

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