The Problems in Making Jewelry from Old Gold

April 16th, 2011 by James L. Sweaney, CGA, FGA. GG
Custom Wedding Band and Original

Custom Wedding Band and Sample of Original

Earlier this week, we delivered this nice 14K rose gold custom gent’s wedding band to a very happy client. It was made as a replacement for the original wedding ring belonging to her husband, to be presented at their upcoming anniversary.

From what our client told us, two uncles had combined their gold jewelry, one of whom designed the ring, created the wax and melted the “old gold” to make the ring, which was presented to the couple as a wedding gift.

Over the years, the gold darkened, and eventually broke into pieces. A broken fragment of the original (to the left) was our sample to recreate the design. Our job was to reproduce the original as closely as possible.

We showed our client a number of gold alloys to see what was closest to the original color– she chose our 14K rose gold. From there, our CAD/CAM whiz, Jenny, was able to reproduce the original pattern quite closely. When our client saw the new ring, she burst into tears of joy!

From our years of experience, the breakdown of the original was completely understandable. Melting “old gold” to make new jewelry is not the best practice of jewelry making for several reasons.

First, karat gold alloys are made with a specific use in mind. The manufacturers of gold alloys pay metallurgists big dollars to precisely engineer their alloys for color and use, then jealously guard these recipes as proprietary trade secrets– some alloys, like Peach Gold, are even patented.

While the percentage of gold remains the same– today’s 14KĀ  gold is always 58.5% gold– the 41.5% of alloy metals can be very different depending on the intended use. Karat gold used for casting has zinc and sometimes silicon added to improve the flow characteristics, while gold alloys used for rolling and stamping are designed for strength and workability.

Next, the color of the karat gold depends on the alloy metals added. In 14K white gold, nickel is added to bleach out the yellow of the gold, while yellow and red golds are alloyed mostly with copper and silver. The 14K rose casting gold we used for this ring contains about 25% copper, hence the reddish coppery color.

Additionally, solder joints, repairs, and the uses of the gold object over the years introduce impurities into the gold jewelry.

Finally, the process of casting changes a gold alloy slightly. The zinc in the alloy begins to boil off as vapor when the gold is melted– thus, the karat of the cast gold increases slightly. For this reason, we always add at least 50% new gold alloy to all of our gold castings to compensate for this imbalance.

So you can see why the gold alloy in the original ring did not stand the test of time. MeltingĀ  pieces of old gold together and/or not adding newly refined gold creates an alloy that is unpredictable and inherently unstable. In this case, the ring discolored drastically and became so brittle and porous that it broke– something we don’t see with properly crafted gold jewelry.

We get asked all the time to remake old gold into new jewelry, and our answer is always the same. We don’t make jewelry from old gold because there is no way to guarantee the quality of the product.

We completely understand the sentiment and attachment people have for the gold handed down thru their family or for pieces they have worn for years– we have pieces like this ourselves– but we know it is not a good idea to reuse the gold as is.

What we will do is offer our clients a fair market price for their gold plus a 20% bonus over that cash value if they use the proceeds in our store. We send this gold to our refiner who refines it into pure 24k gold, then sells it back to us as freshly refined properly balanced and alloyed gold, ready to be made into new pieces.

Our name is on the work, so we proudly stand behind it by maintaining the highest quality and best practices possible.

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