Andrew Dougherty Tax Stamps 2 Cent Stamp: RU2aDie Approved April 20th, 1865First Issued May 1865Last Issued July 17th, 1866Material Old Paper800,500 Issued 4 Cent Stamp: RU3aDie Approved Oct. 18, 1864First Issued Dec. 1864Last Issued Sept. 11th, 1866Material Old Paper515,250 Issued RU4a, Old Paper RU4u, Ultramarine, Silk Paper RU4b, Silk Paper RU4c, Pink Paper 5 Cent Stamps: RU4a, RU4b, RU4u, RU4cDie Approved August 21st, 1866First Issued August 1866Last Issued 18774,631,985 Old Paper Issued7,638,947 Silk Paper Issued179,496 Pink Paper Issued 5 Cent Stamp: RU5dDie Approved Jan. 16th, 1878First Issued 1878Last Issued Feb. 15th, 1883Material Watermark Paper7,980,983 Issued 10 Cent Stamp: RU6aDie Approved Oct. 18th, 1864First Issued Dec. 1864Last Issued May 2nd, 1866Material Old Paper442,700 Issued Toppan, George L., et al. An Historical Reference List of the Revenue Stamps of the United States: Including the Private Die Proprietary Stamps. Castenholz, 1990. SCARLETT, Oscar. A Complete Cyclopædia of All the United States Revenue Stamps: Including Document, Match, Medicine ... and Other Tax or Revenue Stamps. William E. Scarlett, 1893.