Choosing Which Metal To Use – Part 4

Last time we asked: What about silver plate, silver filled, vermeil, and gold filled metals and sources of metal?

I only use solid silver in my shop for cast pieces, plate and wire. The differences in cost between silver plate, silver filled, and solid sterling silver metal is, in my opinion, not sufficient to warrant using the less expensive metal. If I am using wire to make a knit chain necklace, the cost of the metal is important, but the majority of the cost is actually in the labor. Some of my less expensive bracelets and necklaces may have silver plated clasps.

Vermeil is sterling that is gold plated. This term is rarely used outside of the United States. I use vermeil, gold filled, and gold plated clasps for necklaces and bracelets. Vermeil is the same thing as silver gilt or gilt silver which was a very common period technique. Medieval people often could not afford solid gold items either. Gilt bronze was often used, especially for large items, like bowls and reliquaries.

English: Reliquary from Limoges, France, c. 12...

English: Reliquary from Limoges, France, c. 1280-1290, champlevé on gilded copper, Honolulu Academy of Arts (Photo credit: Wikipedia)

 

 

 

 

 

 

 

 

 

With the price of gold over a thousand dollars an ounce, solid gold is too expensive for your average customer. Gold Filled wire allows me to create affordable “gold” knit chain necklaces. Filled metal has a physically bonded layer of precious metal that is much thicker than plating.

English: Diagram of gold filled jewellery

English: Diagram of gold filled jewellery (Photo credit: Wikipedia)

 

 

 

 

 

 

 

 

 

 

 

 

And what about sources of metal? Any reputable metal distributor in the USA will be able to give you the actual metal content of an alloy. This is important for a number of reasons. The lead laws are one, but knowing the metal content of my supplies can be very important to my customers. Metal allergies are not that uncommon. By keeping an alloy list in my shop I can easily answer people’s questions about whether they can wear something or not. Most people will turn green from any copper alloy, I know that I certainly do, but some folks get serious contact dermatitis from nickel and other metals.

The vast majority (about 95%) of my metals come from a green US company that guarantees the metal content of their alloys. This is a serious benefit to me when I am developing new products. Each metal has very specific attributes. How much can it stretch or bend before it cracks? If I draw the wire down, will it become a lot harder and springier, or just a little.

I know people who enjoy making their own alloys, and the best of them have considerable knowledge in metallurgy. Knowing what is in the metals that you are alloying is critical. Using random bits of metal can create unanticipated issues, including lead content. I often wonder, when I see the prices of some of the items coming out of the former Soviet bloc countries, just what the metal content is. When a cast piece is selling for less than my cost to produce it, it makes me wonder. I think I will stay with guaranteed alloys from US companies!

Choosing Which Metal To Use: Part 3

Last week we asked if there were any other issues with metal that we should consider. Well, two things come to mind immediately: metals other than bronze and lead, and knowing your metal source.

Metals were not carefully assayed in the past they way they can be today. The people who created the various pure metals and alloys were knowledgeable, and there is a considerable amount of pre-1600 written material about creating various alloys, but metal purity could not be tested with the same level of precision that we have modernly. Many alchemy texts have information on metallurgy.

When you are reading museum data base entries, the actual metal content of a piece is rarely listed. “Copper alloy” is often used to refer to any sort of bronze metal and the actually purity of precious metals is rarely noted. Until recently it has been much too expensive to test each piece to determine exactly the metal content. Larger organizations, like the British Museum, will sometimes reevaluate pieces as they clean them, and they sometimes test the metal content. Testing content has helped to reveal frauds, and modifications of artifacts, many of which were done in antiquity.

For anyone who has ever followed the types of silver that are available modernly, the two most common would be Sterling Silver (also designated as .925) and Fine Silver (.999).  Those numbers simply indicate the percentage of silver that is included in the alloy. There are other designations, including coin silver (which varies in silver content depending on the date of manufacture and the country), and Argentium Silver (which is a tarnish resistant form of Sterling Silver with special properties). The terms Bali Silver, Thai Silver, and Mexican Silver may be used in a retail setting, but have no legal meanings. Nickel Silver, or German Silver is silver colored, and does not actually contain any silver at all. It is a copper alloy.

There were an assortment of silver alloys that were used in period that are not usually used modernly. Billon has been used since at least ancient Greece. It is a silver colored alloy which usually contains silver and other metals (usually copper), and may sometimes contain mercury. It was commonly used for making coins and medals. Electrum is a naturally occurring alloy of silver and gold, which has been used since at least 3,000BC by the ancient Egyptians. It was used widely in coinage and jewelry manufacture by cultures as varied as the Egyptians and the Vikings. There are major deposits of natural electrum in Anatolia (Turkey).

All of the silver pieces that I currently make for sale in my shop is classified as Sterling Silver. My cast pieces are solid sterling, and the wire and plate that I use in my toiletry sets, needles cases and chains (both knit and link) are all solid Sterling Silver.  I do not currently work with Argentium silver. Sterling Silver alloy was used during Medieval times.

Next time: What about silver plate, silver filled, vermeil, and gold filled metals, and sources of metal?

Dealing with Sterling Silver Jewelry Shapes that are Difficult To Polish

Dealing with sterling silver jewelry shapes that are difficult to polish can be challenging.

Yesterday I was working on a large sterling silver jewelry project – a coronet for a friend who is a historic re-enactor. There are a LOT of differences between working on small pieces of jewelry, and working with something this large. And that reality prompted me to make a couple of quick tools to make the polishing safer and more effective.  As I was working, I realized that a couple of the things that I had figured out might be of use to others, so here are two quick tips for polishing large objects.

The sterling silver jewelry piece that I was working on was challenging because it was large with lots of pointy bits that made it waay too dangerous to polish on a big polishing wheel. The opportunity for it to catch in the wheel and either do damage to me or the piece was a serious concern. So that meant it was time to haul out the flex shaft for finishing! But how to hold and polish the piece at the same time? The piece is essentially a large oval, made from a strip of sterling silver one inch wide and 25 inches long. The band is decorated with sterling silver annulets (think donut shapes) and a specialized form of a sterling silver cross with a pointy bottom and exaggerated pointy arms. The annulets are completely soldered flat to the band, but the crosses stick up above the top of the band with all of their pointy goodness just waiting to hook onto any polishing wheel that comes near them. I often polish smaller pieces by simply holding them in my hand, but that was NOT going to work for this large piece of sterling silver jewelry (well it’s more of an accessory than what we think of as jewelry). I am fortunate enough to have a jewelers’ bench in my Studio, so I put padded bench pinthe bench pin into the front of the bench. Now for those of you who don’t have something like a bench pin, well, I would probably lay a chair down on the floor on its side, sit on the floor or a stool, and use one of the legs as a support. The chair leg can serve the same function as a bench pin in this application.

I always have a pile of those white terry cloth shop towels in my Studio. They are inexpensive, and handy for everything from spills to padding, which is exactly what I used one for! I folded the towel in half, wrapped it around the bench pin   and then held it in place with some masking tape. Now I had a clean, slightly rounded and padded, non-scratch support (a temporarily modified bench pin) that I could rest my massive sterling silver jewelry on for polishing. If I were using a chair leg, the towel would protect the chair and give the same kind of padding ( I would NOT do this with grandma’s valuable antique chair, just in case). The piece, remember it is a large oval, could literally hang on the towel-covered bench pin (or chair leg) and easily be held in place with one hand while I polished it with the other. There is another seriously important aspect to this arrangement. When it coronet on padded bench pinwas time to polish the tops of the sterling silver crosses, even the flexshaft wanted to hook onto and dance around the piece. Solution? Press the top of the crosses down into the towel just slightly. The polishing buff could easily do its job on the front of the crosses without catching the edge of the piece. It does get the towel dirty, but that is what those towels are for – they are called shop towels for a reason!

My goal when I whipped up this quick little modified bench pin support was three-fold – protect me, protect the piece, and allow me to polish the piece until the sterling silver gleamed. Mission accomplished! I hope this gives you some ideas for making your own workshop safer and more productive! I’ve included a picture so you can see my “high-tech” support system and what the sterling silver piece looked like while it was being polished. Enjoy!

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