Assuming the green is a deposit from something cupric and not copper under the surface of the coin. (The coin being fine silver). Worn in this condition, its worth what someone is willing to pay for it like all ancient coins. Rarity, well I would say it's rare enough. The likely hood of you going to a coin show and finding one or more to choose from is remote. You can find a few online. If I were to assign a value to it I would suspect somewhere around $50 US.Hope this helps.
Disclaimer: While a tremendous amount of effort goes into ensuring the accuracy of the information contained in this site, Coin Community assumes no liability for errors. Copyright 2005 - 2026 Coin Community Family- all rights reserved worldwide. Use of any images or content on this website without prior written permission of Coin Community or the original lender is strictly prohibited. Contact Us | Advertise Here | Privacy Policy / Terms of Use