If you really want it, it could be worth ten times that amount. Only you can decide what it is worth to you.
On the other hand, if you are asking does the metal content have a trade value in excess of $15, the answer is no. In the UK I bought today a Victorian double florin - that's .925 solid silver, eight times the weight of a six pence - for $44 (or the equivalent). Not that I was buying metal, I was buying a coin, but it gives you an idea of the value of the silver (the Rhodesian six pence was the same wight as the British, and all British coins at the time were related in weight and value, so two sixpences weigh the same as one shilling, which weighed half as much as a florin, which weighed half as much as a double florin etc).