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CONT: Terms, charcoal plate and coke plate, which in last century described quality of iron used as a base metal have now come to be applied to tin plate of certain coating thickness. Amount of coating on coke plates is generally between 1.24 and 2.5 pounds per base box - on charcoal plates between 3 pounds and 5 pounds per base box.
CONT: Tin Plate. ... When coated by the hot-dip process, the tin plate was termed coke tin plate or charcoal tin plate. When coated by the electrolytic process, it is termed electrolytic tin plate. ... Hot-Dipped Tin Plate. Tin plate formerly was produced by the hot-dip tinning of thin plates that had been hammered or rolled from bars of puddled iron. The pig iron used in pudding might have been made in blast furnaces using charcoal or coke as fuel. Plates made from ""charcoal iron"" were considered a more ductile and higher grade product; hence, tin plate made by coating charcoal-iron plates with tin (charcoal tin plate) was regarded as a product of higher quality than tin plate with a coke-iron base (coke tin plate). At present, the designation ""charcoal tin plate"" merely indicates plate with a relatively heavy tin coating as compared with ""coke tin plate"" as described below, and has no significance so far as quality of the steel base is concerned.
OBS: Various grades of hot-dipped tin plate were produced, the terminology indicating in a general way the weight of tin coating or, more exactly, the amount of tin used to produce the given unit or base box of plate. Coke tin plate has always designated the plate produced with the lowest amount of tin and formerly was called Cokes or Common Cokes. In ascending weight of coating, the various grades were Common Cokes, Standard Cokes, Best Cokes, and Kanners Special. Charcoal tin plate carries still heavier coatings including 1A and 2A.