These ocean quahog shells are brown with no purple on the inside. They are from the North Atlantic. Also called Icelandic cyprine, mahogany clam, mahogany quahog, black quahog, and black clam shells.There are specialist names for different sizes of this species of clam. The smallest clams are called countnecks, next size up are littlenecks, then topnecks. Above that are the cherry stones, and the largest are called quahogs or chowder clams. The shells have been shucked and cleaned in cold...