I'm not suggesting you munch on a pair of 24-carat gold earrings or a sterling-silver bracelet, but these precious metals are edible, within reason. What are they? Food-grade gold and silver products are made from the pure metals. Because they have no flavour, odour or nutritional value, the metals are used as decoration and, especially with the more expensive gold, for the 'bling' factor. How are they available? They are usually pounded into extremely thin, delicate sheets that are layered between tissue paper. The metals are also available as gold or silver 'dust' and flakes. What else? Gold flakes are used in spirits such as Goldwasser vodka. Gold and silver leaf can be purchased from some Indian food shops and from high-end pastry suppliers. How to use: the best way to apply gold and silver leaf is with a small, soft brush - peel back the top layer of tissue paper and use the brush to pull away a small piece of the leaf from the main sheet. Pick up the piece of leaf with the brush, transfer it to the item being decorated and gently press it down. Flakes should also be applied with a brush. Both metals look especially good when contrasting with shiny, dark chocolate glazes. Gold or silver is made into a fine dust that can be used to give a subtle - or not so subtle - gleam to chocolates. The dust can be used on its own or in conjunction with cocoa butter, which helps it stick and makes the dust seem more vivid. For moulded chocolates, wash the moulds with very hot water and dry them thoroughly, including each indentation, with a soft, non-abrasive cloth; if the moulds are dirty or scratched, the chocolates will stick. Brush a very thin layer of melted cocoa butter evenly into the indentations then dip a small brush into the gold or silver dust and gently tap some into the moulds; this gives a subtle sparkly effect. If you want a stronger effect, let the cocoa butter dry then dip the brush into the dust and brush some of it directly over the cocoa butter. Fill the moulds with tempered chocolate and ganache and let them set before unmoulding. If you're working with hand-dipped truffles rather than moulded chocolates, brush the gold or silver dust directly over the surface of the tempered chocolate after it sets.