Beautifully engraved certificate from the Detachable Bit Corporation of America issued in 1930. This historic document was printed by Masbrouck Thistle Co. N.Y. and has an ornate border around it with a vignette of men working underground in a mine with with a drill. This item has the signatures of the Company's President, J. B. Shearer and Secretary, A.C. Vivian and is over 75 years old.
Certificate Vignette The company was found in 1926 and made the Thurston Detachable Bit.