Leading cause of split and cracked coins 0

[RWB]

This should help identify a cause of split coins. Instead of a bubble, the inclusion could be copper oxide from melting/annealing or a grain of  metal that go on an ingot or strip. It's unsusal that the defective quarter was returned -- possibly he requested this.

Samuel P Duffield, M.D. PhD

Dearbornville, Mich

 September 27, 1880

 Sir:

            I have received your letter of the 24^th instant, transmitting a quarter dollar supposed to be counterfeit.

            The coin is genuine. The want of sonority is caused by a flaw or split in the piece which I have furthered opened.

            A flaw of this character is occasioned by a minute air bubble formed in the ingot in casting, and subsequently spread out in the rolling process. The piece is herewith returned.

            Very respectfully,

            R. E. Preston,

            Acting Director

Edited December 17, 2022 by RWB