Possible Clues:

• Roman coins
• Ancient Roman coins
• Silver coins of ancient Rome
• Ancient Roman silver coins
• Ancient coins in a dire new form
• One country starts to excavate, digging up old coins
• Old coins coming from drain, ie rubbish
• It's expensive to keep any number, so having two Roman silver coins
• Many asses could be procured in exchange for this Roman coinage
• Old Roman coins