Hallmark 999 or pure silver. This type of silver is mostly used in investment pieces such as coins and bars or bullions. Pure silver also has technical uses.
Hallmark 925 or sterling silver. This is the main alloy used in silver jewellery. Additionally, hollowware (goblets, trays, candlesticks) is produced from this alloy.
Hallmark 830. Silver alloys with this purity range are commonly used for making silverware.
Hallmark 800. Back in the day, this kind of silver was mostly used to produce silver items.