The One Hundred Pounds (£100) coin is a coin denomination issued by the Royal Mint since 2015. The format is used to mark special occasions or themes and is not intended for general circulation - which is served by a banknote of the same value instead.
The coins contain two ounces of silver (with weight slightly differing from the silver 2oz bullion coins issued for investors), but are distributed at face value - which is much higher than their intrinsic value, making them technically non-circulating legal tender (NCLT) and not bullion.
The coins are legal tender, but contrary to popular belief this does not mean that banks and retailers automatically have to accept them (in practice, they do not accept them).
This is the second coin from a new series of silver coins known as the Landmarks of Britain, and features Buckingham Palace, the London residence of the British monarch. The reverse design was first issued in 2014 as a colourised £5 coin.
Designed by Royal Mint engravers Laura Clancy and Glyn Davies, each attraction is viewed as though through the eyes of a visitor, seen through passing crowds or rain showers, giving the coins the feel of an impressionist painting, enhanced by the trichromatic colour-printing. | 
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