I would place an ad where i found it for "Money found, contact me at *** *** **** and then the person would have to tell me how much money they lost, and what it was packaged in. If the person got it right, then i would return it. I would give at least a month, for the person to claim their money. If nobody claimed it properly, then i would put half in the bank for intrest, and then would spend a quarter, on stuff i want, and a quarter on some charity, or charitible thing.
This is the truthful way i would deal with it. For all i knew, it could be the last remains of some old persons savings, which they withdrew, for some critcal operation, or for safe keeping. Anything over 100 dollars, i would certainly try to find its owner. Less money, is not even practicle to try to find the owner.