Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The five ounce (5 oz) silver coins are denominated as ten pounds (£10).
The coins are legal tender but are not intended for circulation. They are targeted at bullion investors or collectors who appreciate the special editions as pieces of art. The coins are typically "one-year" types usually issued in parallel with smaller denominations with the same reverse designs.
The 2018 Year of the Dog bullion coins are part of the Royal Mint's Shēngxiào Collection - a coin series dedicated to the Chinese Lunar calendar.
As the mint says:
"For centuries The Royal Mint has drawn upon its unrivalled heritage, experience, and craftsmanship to evolve and meet the needs of an ever-changing market. In 2014 we struck the United Kingdom’s first Chinese Lunar coins, introducing a new series and a United Kingdom first. The Shēngxiào Collection, named to honour the Chinese zodiac, is a celebration of the UK’s diverse multi-cultural society. At Chinese New Year, gifts and tokens are exchanged, particularly the gift of money in red envelopes, symbolising good wishes for the recipient’s health, wealth and prosperity. These Lunar coins from The Royal Mint embrace this globally observed tradition, lending a unique British angle to an ancient tradition."
"People born in the Year of the Dog are loyal and observant. They are trustworthy and can always keep a secret. Just as pet dogs are considered loyal companions, people born in the Year of the Dog are said to be true and dependable friends and they can’t do enough for the people they are closest to. While they can jump to conclusions, they are generally straightforward and friendly people.
Dogs are honest, friendly and compassionate, careful and practical, but as they are not very good at communicating, it is tough for them to express their thoughts to others. They have a good nature, meaning that they tend to do things by the book and follow the rules. They like a quiet life and a close family relationship makes them happy and content."
The five-ounce silver coins were issued boxed, in Proof FDC grade only. | 
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