Hello! I have just recently started looking into military pins and medals and I remembered I had these from a box I bought several years back. I have identified most of them but would like possibly to learn what era they are from and if they are in fact authentic. Marksman Medal for Pistol-D (Dismounted Pistol) (Era: <=1948). The Medal is embossed STERLING. The bar is stamped STERLING. 1st Lieutenant bars (era?). Each is embossed STERLING. 2nd Lieutenant bars (era various?). Left to right: No markings, gold-tone pin. No markings, steel-tone pin. No markings, more complex steel-tone pin. Embossed AULD COL O, dark-tone pin. Engineer Corps Officer's lapel pins (era?). Stamped "ACIDTEST", detailed castle door. More Engineer Corps Officer's lapel pins (era?); All unmarked. Bottom left is slightly shorter than the other two.