To collect and deposit, as money or other valuable things, for future use; to lay up; to hoard; usually with up; as, to treasure up gold.
a collection of precious things; "the trunk held all her meager treasures"
Any old gold or silver coin or other object which has been found together with others in a hoard. In Britian, to qualify as "old" an item usually needs to be over 300 years old, occasionally 200. The precious metal content can be as low as 10% by weight. Single items are excluded. There is a precise legal definition in the "Treasue Act 1996", which replaces the old "Treasure Trove" laws.