What is the difference between the alloys you use?
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Sterling silver
Sterling silver is commonly stamped with 925, meaning that it is an alloy where 92.5% is fine silver and the rest is mostly copper, with sometimes small amount of other metals such as zinc. Whenever we made an alloy in goldsmithing school, it would only be fine silver with fine copper. In Germany, it is almost impossible to find 925 sheet material or wire to purchase, as since several decennia the use of a 935 alloy has become the standard. I purchase my 925 Sterling silver materials mostly from the Netherlands. The 935 alloy consists of 93.5% is silver, with the rest copper. My German supplier claims there are no other trace metals, but I can’t guarantee it. It is not an official term, but to differentiate between 925 and 935, and 935 Argentium, I will call the German 935 alloy Sterling+ on my website.
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Argentium silver
Argentium silver (93.5-96% fine silver ca. 1.2% Germanium and the rest copper) was developed by goldsmith Peter Johns and colleagues in the UK in the 1990s. The Germanium content inhibits the copper from reacting in the silver, making it tarnish resistant. This alloy is particularly interesting for people who regularly experience allergic reactions to wearing Sterling silver which is likely caused by the copper content. If your allergen is silver however, it obviously will not work. At current I can get 940 alloy as sheet with 935 Argentium for the wire. I will differentiate 935 German alloy with 935 Argentium on the website by adding the word Argentium. When using Argentium, I need to make earring posts and backings from scratch (no findings available). Argentium silver is altogether softer and whiter than the Sterling alloys and requires completely different procedures to work with.
This makes it slightly more expensive in comparison to Sterling Silver.
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14 and 18 ct Gold
Yellow 14 ct gold is an alloy of 58.5 to 58.8% gold, 12.8 to 14.4% silver, 22.9 to 24.8% copper, 3.5 to 4.1% zinc and traces of cobalt. It is harder than 18 ct gold, but can cause more allergic response in people sensitive to copper. It is for example not advisable as a piercing. It is hallmarked with 585. Below this section I will add another caveat.
Yellow 18 ct gold in contrast, is 75% fine gold, 12.5% silver and 12.5% copper. It is hallmarked with 750. Other colours of alloy vary in composition. If I were to make gold earrings, I would prefer to use 18ct for less allergic response.
Most people will be familiar with Sterling silver (925/1000), but less so with the silver alloys that I described above. I always loved silver and lighter coloured alloys (i.e. white gold) more than yellow or red gold, although I love to use gold in accents and fine gold when I made some Japanese mokume gane alloys (currently no possibility to make that, perhaps in the future). I’ve had most experience with Sterling silver, Argentium is a fairly recent discovery I made.
I think each alloy has its benefits and downsides, making one better suited for intended purpose or type of jewellery than the other. For example, 925 Sterling silver is slightly lighter than the other alloys - as silver has a higher density than copper. It is slightly harder and more durable for example, when used as a bracelet or a beltbuckle. The alloys higher in silver content are heavier, a bit softer and a bit whiter - and might be easier to combine with autogenous welding (fusing without solder). Argentium silver is more malleable (loved most by silversmiths who create tableware for example). It is a novelty material, that yes - requires barely any re-polishing afterwards - but it is also limited when you would like to apply oxidation to bring out details.
It requires a hardening process of 2-4 hours in an oven, and can break if annealed in a way that sterling silver is annealed. Therefore, should any future repairs or adjustment be necessary on Argentium silver, it is important to note to the jeweller that it is Argentium. Not all goldsmiths are familiar or experienced with working with this material, but it has gained some popularity in the USA. In my impression, Argentium silver still remains a bit softer after the “hardening process” in comparison to Sterling silver. I will experiment on it further, but for the time being will apply it mostly for earrings and pendants.
Sterling silver used to be the alloy that one of my instructors would use for creating wedding band models for demonstration purposes of how it would like in gold . It was the “cheap” material, lower class and a bit cumbersome to work with in comparison with gold that allows for more local heating and soldering (and where autogenous welding is easier, especially with 18ct).
I think right now, silver not only allows for more creativity but might make an entry as an alternative for wedding rings for people with a lower budget (perhaps in combination with gold or the Korean technique Keum-Boo which is applying gold sheet to silver, then oxidizing the silver). I will not use gold vermeil because of their limited durability, but I might use Keum-Boo in the near future, as the combination with oxidation will likely not lead to increased polishing in the years after. On a ring, it would still wear down faster than in earrings.
