Civil War Dragoon Eagle D Coat Button Beautiful Uncleaned Patina

Nice non dug Union Civil War eagle D coat button. It has a beautiful uncleaned patina. The front of this dragoon button has a spread wing eagle with a capitol D in the shield on its chest. The reverse has a c.1860 small depressed HORSTMANN & ALLIEN . NY . backmark and a straight shank. It measures 21 mm's in diameter. It is a great button. $110