This button is listed simply as "CLAW. A pierced design mounted over a metal background; two piece. $1.00" in Hughes & Lester's The Big Book of Buttons (1981)— Plate 273, #30, pp. 620-21 No other information (age, origin, etc.) is provided.
I believe this would be from a 1820-1854 army "great coat". Probably a Scovill or Waterbury mark on the back? But there are many here wiser about these things than myself. Welcome to TreasureNet!