According to the Treasure Act 1996 this ring would be classified as treasure, and thus the finder would be compelled to first offer it for sale to a museum ("that belongs in a museum"). Only if no museum wants to buy it can it go on general sale.

This ring would fall under the definition:

>Any individual (non-coin) find that is at least 300 years old and contains at least 10% gold or silver.

None of this is mentioned in the article, which makes me think some information is missing... It's possible that no musem wanted to buy it at £40K.