Diamond Calk Horseshoe Company

The Diamond Calk Horseshoe Company of Duluth, Minnesota, USA was founded in 1908 by blacksmith Otto Swanstrom.

Initially manufacturing horseshoes with a special type of calk to improve the animals' foothold on slippery surfaces, the company successfully adapted to the development of motorised transport for the masses and produced a range of adjustable wrenches and pliers from the 1920s. The family-owned company was sold to the Triangle Corporation in 1981; Triangle itself was eventually sold to Cooper Tools.[1]

In 1994, the last workers vacated. The building was demolished in 1996.

Gallery

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  Early 8" adjustable wrench manufactured by the Diamond Calk Horseshoe Company
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  Early 8" adjustable wrench manufactured by the Diamond Calk Horseshoe Company: opposite side showing manufacturers marks
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  Diamond Calk Horseshoe CO. 8in adjustable wrench

References

1. Norton, Maryanne C.; Aubut, Sheldon T. (2001-07-30). "Diamond Calk Horseshoe Company". Duluth, Minnesota. Arcadia Publishing. p. 54. ISBN 0-7385-1891-3.