Roman times.... are you in Italy or Europe? I've been prospecting alot in the last 6 years. Not really an EXPERT yet. That being said, the pics look good to me. Try down stream from where the mine was. Is that river gravel in the pic (white rocks) ? In AZ, the red dirt is said to be best. Red dirt here has more clay and harder to work. I like the sandy soil..... like your pics. I would try classifying up to a bucket (5 gallons ) into a pan. If no "color" try elsewhere. If there was a mine, there must be a mine dump nearby. Some people call the dump "tailings". Look for the dump to ascertain that it was a mine. No dump means no mine. TTC