Recently I made a homemade gold alloy, against the recommendation of the very helpful people on this site. Now it seems to be coming back to bite me…
The alloy I used was a 14K rose gold with:
58.5% gold
5% Silver
36.5% Copper
I used .9999 fine gold from Canadian PMX aswell as .999 fine silver from the same company. My copper was copper wire from the hardware store. I was under the impression hardware store copper electrical wire was always .999 copper maybe with some oxygen and so little scope for contamination in the alloyed gold. This was apparently however not the case.
I am wondering if maybe you cannot roll rose gold? Almost everywhere I’ve looked says that rose gold can be pain to roll or even cast with. Regardless the alloy I made behaves like it had impurities.
The finished rose gold was poured into an ingot then I went on to roll it. I would roll it gently 2 or 3 times, anneal roll again a few times anneal and on the third round of rolling it would always form a mosaic like crack structure. This was NOT the normal cracks from rolling that you get, this performed like when a I tried to melt some pendants without removing solder. An alloy with impurities.
I tried annealing less often, more often, quenching while still red but nothing seemed to work. It would always form the cracks after about three rounds of rolling. I managed to get some wire as the cracks were not very deep. If anyone would be able to tell me what I did wrong and tell me source for very pure copper or master alloys for rolling I would greatly appreciate it.
I have made homemade gold alloys before. A 14k green gold alloyed with sterling as a master alloy and a 10K by adding copper (different source) to said green gold alloy to make it yellow. Both seemed to roll great and so I don’t know whether it is the fact it is rose gold, impure copper wire or something else.
Your metal needed to be quenched immediately once solidified in your ingot mold to prevent large grain structure from forming. It is along these grain boundaries that the metal is now showing the cracking you are experiencing. Legor sells rose gold alloys specifically
designed for mechanical work as well as pure copper for alloying purposes. HTH
I think that’s the percent of copper that you used seems high. I pour almost all of my golds, yellows, whites and rose. I never quench in ingot but I do forge them first. I use a 14k rose from AAA in Portland OR. Don’t often have cracking issues. I draw wire from ingots or roll flat sheet. And forge rings. Maybe the high amount of copper can be reduced in your next try.
Thanks for the response. I tried quenching it while red hot and the cracks still appeared after the second or third rounds of rolling and multiple annealing and not before. I also included 5% silver and it was 14K.
Maybe I could try 33.2% copper and 8.3% silver, do you think that would fare me better? Do you notice customers mind the peachier tone of higher silver rose golds?
So it doesn’t start cracking till its time to anneal and once you anneal the cracks start, true?
Have you tried annealing and quenching in Alcohol? yes plain old rubbing alcohol, of course, it being flammable do take precautions and put your alcohol in a stainless steel container and extinguish ( if it catches fire with a lid ) it works very well with nonwhite gold alloys.
Yes the alcohol quench works really well. I started doing this when pouring ingots and forging them in 14k nickel white gold, which can be stubborn and prone to cracking. I use methanol.
The relatively long, slow quench doesn’t shock the metal like quenching in water does. I always wait for the red to leave and quench at “black heat”.
You can also go straight to the mill. I’m not sure how much regular isopropyl (rubbing) alcohol has in it though….
Safeway, copper wire is not pure. It has selenium for one. Each manufacture will make different formulations of electrical copper wire. Buying it off the shelf as it were, you need to look at the label on the reel they cut it from. I go through thousans of feet of the 6 ga each year. I stick with Southwire. I dont know if this helps. I do use my filings to alloy silver solder for my filigree work and have never had a problem. I dont roll that alloy I file it for what I need.
I have found when rolling lower-karat gold that (1) you can’t anneal too often, and (2) let it air cool on a steel block, do not quench. If you have flanges, cracks or burrs in the metal after rolling, file or sand them off before annealing, especially if you are rolling wire. If you don’t, the burrs just get folded back into the metal, causing it to crack down the road.
HTH,
Makena