Confederacy, New Orleans, La., May 20, 1862. Double ring River Mail postmark tying four margin 1861, 5¢ green, Stone 2 on incoming river cover to Gen. C. Dahlgren at the St. Charles Hotel in New Orleans, Very Fine, a lovely usage of this scarce postmark, ex-Shenfield. Scott No. 1  Estimate $500 - 750. $0 (Image)