An alloy is a homogeneous mixture of at least two metals. When making jewelry, an alloy is made for several reasons and not the pure precious metal processed. On the one hand the workability of the precious metal is improved and on the other hand the color of the precious metal can be influenced, for example a more subtle yellow gold tone or a warm rose gold tone can be produced.

Yellow, red (rose) and white gold are mainly used in the manufacture of jewellery. For my collections I use silver, silver plated and 14 kt yellow gold as standard. On request, I can also make the pieces in other gold colors - get in touch !

The percentage of pure gold in an alloy is specified in "karat", with 24-karat gold being pure gold. 14k gold alloys are 58.5% pure gold and 18k gold alloys are 75% pure gold. The higher the proportion of pure gold, the yellower the color becomes. The gold content can be traced from the hallmark hammered into the piece of jewellery, with either 585 for a 14-carat alloy and 750 for an 18-carat alloy. For sterling silver, 925 (= 92.5% silver content) is hallmarked on the piece of jewellery.

The patina that forms on the surface of silver jewelry over time is also known as "tarnishing". Silver naturally oxidizes; that is, it reacts with sulfur compounds that are in the air and turns black. This is a completely natural process. Many jewelery manufacturers therefore rhodium-plate their silver pieces, which means that the jewelery is coated with a thin layer of rhodium, similar to gold plating. Rhodium is a platinum minor metal. While rhodium plating prevents silver jewelry from tarnishing, it does lose the beautiful silver tone and silver's unique reflectivity, as rhodium is always slightly more greyish and does not have the same reflectivity. For this reason, Gold Coast Vienna's silver pieces are not rhodium-plated as standard. How you can prevent tarnishing or what you can do if your piece of silver has already tarnished can be found under the care instructions .