What should I do with a piece of gold that I found more than three years ago? Should I sell it and use the money for my needs, or sell it and give its value in charity, especially since I don't think I will find its owner?

Whoever finds a lost item must publicize it for a full year. If its owner does not appear, he may benefit from it, provided he guarantees it to its owner should he come. However, if the finder does not publicize it, he must repent and give it as charity on behalf of its owner, or sell it and give its price as charity.

If the finder is poor, he may benefit from the lost item after repenting, as some scholars have stated.