Silver Roman Ancient Help.

The harsh reality of the matter is that ancient coins exist in numbers far smaller than 'rare' US coins but people who want to buy them are even more scarce. Something famous that exists in minuscule numbers like the 1913 V nickel might sell for millions while an ancient rarity that exists in a similar small number will struggle to bring half a million. Modern collectors pay more for the millions of worn Indian Head cents than ancient collectors will for the millions of late Roman bronzes in similar condition. To sell the OP denarius for as much as $15, you might need to find someone who does not know that better looking coins are available. The few thousand serious collectors of ancient coins would be unlikely to buy it at any price simply because we all realize that we can not own every coin we see and we choose to spend each dollar in another way. You might call that attitude 'coin snob' but it is pretty much the same situation we see in US with damaged and poor-fair Barber silver. Numismatic value approaches melt due to lack of demand.