Blackplate

Blackplate is hot rolled or cold rolled,[1] non-descaled sheet steel or sheet iron.

[2] Blackplate is made of non-tinned[2] iron or steel and is annealed on open flames or in an annealing box.

[3] Its dark appearance is caused by its reaction with the surrounding air.

[3] During warm rolling, blackplate can be manufactured to thicknesses of 1.5 mm or more.

[4] Cold rolled blackplate, by contrast, can be made thinner – thicknesses of 0.4 to 1.5 mm being attainable – and produces better surface qualities.