Blackplate definitions

Blackplate

Cold rolled, light-gauge steel commonly used as the base (substrate) for tinplate and other tin mill products.
Found on http://www.metalbulletin.com/Glossary.html

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blackplate

cold-rolled sheet steel before pickling or cleaning. · sheet steel coated with a lacquer or enamel.
Found on https://www.infoplease.com/dictionary/blackplate

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