2019 Scallop Seashell Castaway Collection 1 oz Pure Silver Coin. You’ve heard the story that when you hold a shell to your ear you can hear the sound of the ocean? Struck using 1 oz’s of pure silver this new coin uses state-of-the-art minting and colorizing techniques so advanced and so realistic you’ll swear it is a real seashell. Every coin in the Castaway collection includes a numbered Certificate of Authenticity. Packaging includes woven “beach-mat” collector’s box and a individually numbered Certificate of Authenticity. Credit / debit card.