SILVER
Extraction and Ores
Silver, with the atomic number 47 and symbol Ag, belongs to the transition metals group. Alongside gold, platinum, and palladium, it is recognised and regulated as a precious metal by the Swiss Precious Metals Control Office. In 2023, the leading producers of silver were Mexico, China, and Peru*. Depending on the region, silver is extracted either in its native state or as a by-product, usually from copper or lead ores, such as galena (a lead sulfide ore frequently containing silver).
Like gold, silver is highly malleable and ductile and is typically alloyed with other elements.
Alloys
The silver content in blends recognised by the Swiss Precious Metals Control Office is as follows:
- 999 ‰ = more than 999 ‰ silver
- 925 ‰ = more than 925 ‰ silver
- 800 ‰ = more than 800 ‰ silver
Properties
Watchmaking and jewellery use exclusively alloys containing 925 ‰ silver and 75 ‰ copper. Copper imparts the necessary hardness to silver while maintaining excellent machinability. This blend is commonly known as sterling silver.
Malleable, ductile, and with a bright white appearance, silver is also non-magnetic and has the best electrical and thermal conductivity of any metal.
Silver has been extracted and utilised for over 5,000 years.
With the advent of the first watches, it became widely used in horology from the 16th century onwards.
Silver cases and dials were mass-produced until the early 20th century. In the 18th and 19th centuries, watches with silver cases were typically considered to be of lower decorative quality and were priced accordingly, compared to those with gold cases. The inception of the stainless steel era in the 1930s quickly replaced silver in case manufacturing. Steel is harder, more resistant to oxidation and corrosion, and significantly cheaper, although much more challenging to machine. Silver may still be used occasionally for watch cases, usually as vermeil, which is solid silver plated with gold, thus making it resistant to tarnish.
With the rise of stainless steel in the mid-20th century, the use of silver for cases has become rare. However, silver remains highly valued in the production of dials. Its malleability, bright white appearance, and low melting point are prized by engravers, guillocheurs, and enamellers alike. Today, silver dials are often coated with zapon varnish, galvanically treated (gilding, rhodium plating), or covered with vapour-deposited coatings or enamel (flinqué dials). In addition to being protected inside the case, these surface treatments protect silver from oxidation over the long term.
Although the use of silver in watchmaking is now minimal, the metal is still present in many alloys.