Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The one ounce (1 oz) gold coins are denominated as One Hundred Pounds (£100).
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 2019 Year of the Pig 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 Pig are born leaders; they are easy-going, honest and brave. The Pig is thought of as an intellectual in Chinese culture - a character with a great thirst for knowledge. People born in the Year of the Pig are understood to be inquisitive and intelligent and they enjoy exploring different solutions to problems.
People born in the Year of the Pig are known to be diligent, compassionate and generous. They value friendship highly, never betray their friends, unless in drastic circumstances, and are popular in their social circles. Those born under this sign are punctual and very dependable. They devote all their energy to achieving their goals, because of their great concentration, and they rarely seek help but enjoy helping others. People born in the Year of the Pig are admired for their kindness and are among the gentlest and most selfless of the signs in the Chinese zodiac."
The one ounce gold coins were issued as "bullion" (Brilliant Uncirculated grade), as well as proofs for collectors. | 
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