You ought to publicize it for a full year by using the available media or ads in the city. If anyone comes forward to claim it and gives you the specific description of it, you should hand it over to him or her. If no one comes forward to claim it, you can keep it –  provided you are willing to return it to the owner if he comes for it anytime.

 

Having said this, I should point out: If there is a department or section in the police department, etc. where people entrust such lost articles and advertise it to locate the owners, then you should not keep it; rather it is your duty to entrust it to them.

 

In all such matters, we ought to follow customs prevailing in a culture or society where people turn to find their lost articles or valuables.