Pitkin Flask, ribbed and swirled to the right, 36 ribs, probably Pitkin Glassworks, 1780-1820. Light to medium olive green color, sheared mouth and pontil base, 6 1/2″ tall. This one has an EXCEPTIONAL rib impression and good color, also very nice clarity! Excellent form, and well-executed! It would be tough to improve upon this example.