Period Solder

I could (and will) write an entire paper on this subject. Period silver alloy solder is a mix of silver and copper. (Gold solder is either gold and silver, or gold, silver, and copper.) The fascinating thing about solder is that the melting point of the alloy is lower than the melting point of either of the component metals. For my alloy, I used two parts silver to one part copper, which comes from Theophilus. According to modern sources, alloy solder existed prior to the 12th century. Higgins, in Greek and Roman Jewelry, says that it dates back to the 3rd millennium BC in Mesopotamia. However, we don't have the information about what alloy was being used. Pliny mentions using lead to solder silver, but that's a nonstarter for recreation. That would be considered a "soft" solder, and Higgins distinctly says that hard soldering was known and used. He further says that lead was used to solder silver plate, specifically. Pliny does not mention soldering silver for jewelry specifically. He more talks about it related to statues (probable statuettes) and decorating furniture and larger objects. 

Let me digress here to say that there is extant silver jewelry from Rome. It's not the delicate filigree and wire work that I do, it tends toward chunkier pieces like snake bracelets. There are also "copper alloy" brooches that I would bet money have silver content. The brooches tend to be decorated with chemplevé, which is a form of enamel where the pattern is carved in, rather than built up, as in cloisonné. Despite a severe lack of silver jewelry in delicate styles being found, Higgins posits that more silver jewelry styles are possible and even likely to have existed. There are two issues that I see, one of which is that silver oxidizes. Higgins calls it perishable. The other issue that I posit is that at times, it may have been sacrificed to coinage. It is not unknown for jewelry to have been made from coins, and the reverse is equally plausible. 

Anyway, back to solder. I finally got around to making my own! I did not use the crucible in the photo. I used Cathyn's glazed crucible. I used a modern torch and a graphite rod for stirring. I used tiny graphite molds because my intention is to share. I used an ounce of silver and half an ounce of copper, so it made plenty. Cathyn got a little bar, and I intend to give some to my friend Susanna, as well. Some of it will get filed into powder. Some of it may get hammered into sheet, but the pieces are small enough that that might also not happen. If I can borrow the use of a rolling mill, I will. In hindsight, I perhaps should have used the bigger mold and cut pieces off.

Watching the process of melting was interesting. Even with an acetylene torch, it took a while for the silver to melt. By comparison, it took almost no time for the copper. I was seeing the science in action! The alloy melting temp is lower than the melting temp of either individual metal, so as it came into contact, the copper melted instantly. Cathyn helped by heating the molds while I melted the metal. In a forge, it would be easier to have heat on both simultaneously. We were in a jewelry shop that thankfully had two torches.

The metal poured nicely even though I was shaking badly. Have I ever mentioned that I'm actually afraid of fire? I am. We did pickle the pieces as there was some oxidation on the top. Pickle was absolutely not known in Rome. To that end I also mechanically removed some of the oxidation from one piece. The resulting alloy is still a lovely silver color. 

Next steps: filing and hammering/rolling.

The setup.

The product.

Athenaeum 2025 and the Future

Let me preface this by saying that the event was wonderful! I had many lovely conversations with all kinds of people throughout the day, both about my own work, and about others'. 

This was also the culmination of my project a month goal. I got to display all the works that I've made, along with the inspiration photos of them. If I had had room, I would have included a slideshow of process pictures. I had a lot of pieces, though, and still needed room for the me. Being this prolific, while working a full time job and studying for professional exams (and passing two!) has been a roller-coaster of emotion and stress. But I have learned a lot, and improved my skills in ways that I'm very satisfied with. 

There is so much that I want to do next, but I need to slow down and pick one thing at a time. I'm going to start off by finally making my period solder. Making it will be a matter of minutes, but filing it will be an activity for hours and hours. I won't file all of it. I'm going to give some away, and I'm going to keep some whole for display purposes. I'm planning to make at least an ounce, though (I need to double check the quantity of casting grain I bought), so that still amounts to a lot of filing. 

Once I have the solder, I can test it. See if it works at all, let alone the way I expect it to. If it does, I'm going to start using that as my primary solder. I'm super hopeful and excited about this. I want to remake the Hercules knot necklace. That will be my first real project, if the solder works. I'm going to test it on a simple bronze ring, first. 

Then I'm going to switch focus to research. There are a couple of books I want to get (we are rapidly running out of bookshelf space), and I'm really excited about them. And guess what? They're not about metalwork! I want to research Roman social structures, with an emphasis on slaves, freed people, and women generally. I am actively soliciting book recommendations on these topics. 

And that brings me to Athanaeum 2026, and what I hope to be able to present there: another, smaller selection of jewelry made with my own period solder, and research on Imperial Roman social structures. 

One quick note, the solder that I'm making is actually medieval, not Roman. Pliny says to solder silver with lead, and that's, for several reasons, not going to happen. Silver alloy solder is attested per Reynold Higgins, in his book "Greek and Roman Jewelry". We just aren't given the alloy in a primary source. 

I will leave you with a photo of the event, as well as my earlier test versions. We thought we were going to have 6' tables, and ended up having 8', thank goodness. 

Final display at the event. (Photo by Lissette de la Rose)

First try.

Second try. I think, had I say in front of the table, this would have worked. But in the end, I'm glad I went with the shelves.