Brian, that piece was made in the Cherry St. foundry. My grandfather was the superintendent of the foundry for a few years before he went off on his own. The recipes used by the molders (molders always mixed their own sand in those days) have been lost because modern foundries, with the exception of a very few, have all gone “no-bake” meaning they use resin bonded sand.
Green sand, which wasn’t green, was medium fine silica sand, mixed with cereal flower, bentonite clay, and water. A common practice was to use 10-15% horse manure also. Finer sands could be used in the green sand process which allowed for very good surface finish. Chemically bonded sands require a coarsersand because of the escaping gasses created by burning off the resins.
While our company stopped using the green sand process, it is still used in the art casting shops in France.
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