Precious metals are subject to taxation in most countries, because of their high economic value. In most countries capital gains tax applies when precious metals are sold at a profit. Some countries also apply value added tax to precious metals.
In the European Union, the trading of recognised gold coins and bullion products is VAT exempt, but no such allowance is given to silver. Elsewhere in Europe though, Norway has exempted both gold and silver bullion coins with face value from VAT; Norway is part of the wider EEA (European Economic Area) and thus applies the same "intra-community transaction" rules to all of Europe on a bilateral basis resulting in legally tax-free silver coin availability throughout all of Europe.
Taxation of precious metals Wikipedia
Precious metals are subject to tax as collectibles, with any profit being taxed at the collectibles capital gains rate. This is normally the standard income tax rate, with metal held over 1 year is subject to a maximum of 28%.
Note that many people unfamiliar with the collectibles tax rates (including some well-known websites) incorrectly think that precious metals are taxed at a flat 28% (because they interpret the word "maximum" in "maximum 28% rate").