I started in the jewelry business in 1984, nearly 33 years ago. Part of my job centers on training newcomers as well as cross training existing associates, all while teaching platinum tips and tricks. I perform countless repairs in addition to testing out new products like different types of solders and tools, for example.
Truth is, I didn’t always enjoy working with platinum. In fact, there were times I dreaded the task. But over the years, after finding the tools that work best, I’ve discovered how incredible it is to work with platinum!
IT’S ALL ABOUT THE TOOLS
Your platinum tools should be a unique set.
I can’t over stress this idea. Keep your tool sets separate!
The buffs used to work with gold collect particles that can become embedded in your buffs. These may easily scratch your platinum pieces. By keeping platinum tools separate and well cleaned, you’ll avoid having grit infect your buffing process. Also, be sure to pre-clean the grit from the piece after prepping in order to achieve high polish results.
Here are my recommended tools –
- When soldering a peg head to a shank or an earring post to an earring, use a 1200C solder.
- We recommend 1500C solder for assembling a head to a shank.
- For sizing, a 1700C solder has the best color match and there is less of a chance of solder erosion.
Angela’s Tip: “I personally like to fuse the platinum, especially if I’m sizing up. I add a small piece of stock matching the platinum alloy I’m working with. Then, I fuse these together, that way, you can’t even tell it’s been sized!”
Key Platinum Distinctions:
Iridium is the softest of the three platinum alloys. It is great for rolling and die striking.
- Melting point: 3236°F (1780°C)
Ruthenium is used as general-purpose platinum, great for machining and fabrication, especially in machine welds.
- Melting point: 3266°F (1796°C)
Cobalt is used because of its density and is hardest as a cast. Cobalt is the easiest platinum alloy to work on is the go-to for casting. Its surfaces are smoother than the other alloys when cast, leading to a solid cast without porosity.
- Melting point: 3015°F (1657°C)
With the differences in melting points, avoid fusing these different platinum alloys together.
Things To Know
When working with platinum, many become confused about which alloy they’re working with. If you’re not sure of the platinum alloy, there are a couple of ways to check, one being the stamp.
- Platinum/Iridium should be stamped Pt900.
- Platinum/Cobalt and Platinum/Ruthenium may be stamped just PLAT, or Pt950.
- Of the Cobalt and Ruthenium, a simple magnet can distinguish between the two, as Cobalt is slightly magnetic.
- Don’t use boric acid and/or alcohol as you would with other metals. This can contaminate the platinum and create hard spots.
- Most are afraid of cross-contaminating white gold with platinum. And rightfully so. But sometimes it’s necessary to mix white gold solder with platinum. Stuller carries a 20k white gold solder that flows nicely with platinum.
- Use tungsten and ceramic tools when soldering, otherwise you’ll contaminate your platinum.
- We use large pins, balls, cones, and diagonals.
- We use the L547 solution in the vibratory tumbler.
This creates a burnishing on the platinum, helping to harden the metal. This makes the piece easier to finish. Without doing this, the platinum piece will remain quite soft, causing scratches to stay in the metal and making their removal more difficult.
If you don’t have a tumbler, you can burnish the piece using a flex shaft and a Tungsten-Carbide burnisher or by hand using a hand burnisher. Burnishing the piece will save time when removing the scratches from the prepping process. Also, this process will help to harden the metal, allowing for workability.
When removing porosity:
- Use your tungsten carbide burnishes.
- Be sure to sand and buff stick your platinum.
- Avoid using a coarse abrasive on your platinum. Instead, use a light sand paper.
- Clean before you buff!
By following these easy steps, you’ll avoid porosity reoccurring in your platinum piece.