AG 925, sterling silver, hallmarking and more information about silver
Silver 925, sterling silver
The name sterling silver refers to the British pound sterling from which the former silver pennies, the so-called "sterlings" were made. The number 925 indicates that this alloy is 925 parts out of 1000 pure silver. The remaining 75 parts are Copper, which give the jewelry silver the necessary hardness, since pure silver is too soft for processing.
Like any precious metal used for jewelry processing, silver also receives a stamp with the number indicating the fineness of pure silver in the alloy. The small number is placed on an inconspicuous part of the jewelry. This process is called hallmarking.
All our silver items are made in 925 silver, which is always and guaranteed nickel, cadmium and lead free. This is a requirement of the EU, which came into force over 10 years ago and to which all manufacturers must adhere. In the past, the silver solder used to solder silver had proportions of nickel, but this has long since ceased to be the case.
The gold-plating of silver jewelry is carried out in an electroplating dip. Sterling silver is thereby coated with a thin layer of Gold by electrolysis. The thickness of the layer is measured in micrometers (1 micrometer = 1/1000th of a millimeter). The coating can be made of 24 carat fine gold (999.9 of 1000 parts) or 14 carat gold (585 parts).
Surface treatment of silver jewelry
To give silver jewelry a special look, there are several techniques of surface treatment. When matting, the shiny surface of the silver is roughened by means of a brush. This creates fine structures that run according to the direction of the brush stroke. Roughening also takes place during satinizing, but the effect on the silver surface remains finer and more homogeneous than during matting. Diamondizing gives silver jewelry a distinct rough, grainy texture, the visual effect of which is reminiscent of the sparkle of diamonds.
Silver jewelry tarnishes over time, as silver reacts easily with sulfur compounds from the environment. How quickly this happens depends on several factors. Hydrogen sulfide in the air, as well as organic sulfur compounds that are components of hand sweat, for example, cause the silver to corrode. A bluish-black sulfide layer forms on the silver surface. High humidity additionally accelerates corrosion. It is therefore recommended that silver jewelry that has not been protected by rhodium plating, after thorough cleaning and careful drying, be packed airtight and out of direct sunlight for storage. To protect silver from tarnishing, it is coated with a layer of rhodium. Rhodium is the most expensive metal from the platinum group and has a light, bluish-cold silver tone. It gives jewelry a very hard, shiny surface.