How Do I Know What I am Really Buying? Part 2

Last time we talked a bit about gold and its alloys. This time the topic is silver.

Trivia! Silver was often valued more highly in ancient times than gold because it was less common and more difficult to extract. Gold is naturally found in nugget and crystal form. Silver is sometimes found naturally in conjunction with gold. An alloy of gold and silver, called electrum, was used by 700 BC in coinage, and yes, even the Vikings used electrum.

 Anatolian coins – made of electrum.

The vast majority of solid silver items in the US are made from Sterling Silver. The standard for Sterling Silver in the US is .925, which means that it is 92.5% silver and 7.5% other metals. These metals may include copper, germanium, and other trace metals. The “sterling” stamp is commonly used in the US, but it is also acceptable to use a “925” stamp. Outside of the US the stamp usually says “925”. Like gold, Sterling Silver’s color can vary, depending on exactly what sort of metals are in that 7.5%, but silver is generally valued for its “white shiny” appearance. In fact, the ancient Latin word for silver, Argentum, literally means “shiny”. And that leads us to a specialized form of Sterling Silver.

An increasingly popular form of Sterling Silver is Argentium Silver. This is actually a patented formulation that results in a thin layer of germanium on the surface of the sterling. The germanium layer is tough and resists oxidation- this means that the piece will not tarnish easily. While I know people who work with Argentium, it is still fairly uncommon among small producers, because it is a bit fussy. For instance, you can cool regular Sterling by dunking it in water. If you do that with Argentium silver it will shatter like glass. The Argentium that my metal supplier sells is stamped “935”.

Fine silver is 99.9% pure silver. It is usually stamped “999”, or “999F”. Fine Silver is rarely used for jewelry like rings because of its softness. Many enamelists cast their pieces in fine silver, or use fine silver sheet to enamel on, because it is an excellent base for enameling. The lack of copper in this silver means that there is less danger of the enamels changing color by absorbing the copper. Real glass enamel is colored using metal salts.

Coin silver was a standard in the US for silver coins prior to 1964. This silver is 90% silver, or .90. Coin silver from other countries may vary in silver content.

Terms like Bali Silver, Thai Silver, and Indian Silver have no legal meaning in the US metals market. The item must be stamped with a legal stamp to have meaning. I know merchants who sell Balinese silver that is guaranteed to be 925. And it is all stamped  925.

Company hallmarks can often be used on historic silver pieces to determine the actual type of silver that was used. This is an art in and of itself, and many books have been written on this topic, so I will not be discussing it.

Next Time: Well it looks like silver, but is it?

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?