Is it permissible for me to benefit from money that I found and sold before a full year had passed from its public announcement, knowing that I kept the money, or must I donate all of it?

The ruling on this bracelet is the ruling on a lost item (Luqata). Whoever finds a lost item is obliged to announce it for one year in the place where it was found and where its owner is likely to be. If its owner comes and identifies it, it should be handed over to him. It is not permissible to benefit from a lost item before one year has passed. Your selling it before a year has passed is a wrongdoing, and you are responsible for guaranteeing it. You must announce it by mentioning some of its descriptions in places where its owner is likely to be found. If its owner comes, you are obliged to hand over an item similar to this lost item or its value to him. As for the money in your hand, you may dispose of it by spending it on yourself or giving it to someone else, unless you fear that the owner of the lost item will come and you will not have money to buy something similar to his right.