Platinum is a dense, white precious metal that is highly resistant to tarnish and corrosion and is valued for jewellery, watch cases and scientific uses. It is harder and heavier than gold or silver and keeps its bright grey-white colour indefinitely, making it ideal for securely holding diamonds and other gemstones.
Platinum was known to pre-Columbian metalworkers in South America but was not studied in Europe until the eighteenth century. Its very high melting point made it difficult to work, and only with improved refining and hotter torches in the nineteenth century did it become widely practical. From the late nineteenth century it transformed fine jewellery, allowing the delicate lace-like settings of the Edwardian garland style and the crisp geometry of Art Deco designs. In ceramics, platinum was the basis of the so-called silver lustre used on English earthenware in the early nineteenth century, giving the effect of silver at a fraction of the cost and without tarnishing. In the United Kingdom platinum has been hallmarked only since 1975, so earlier pieces may be unmarked or carry simple stamps such as Plat or PT.
