The designation number for each crucible shall consist of not more that three letters, indicating the type of crucible followed by a number indicating its nominal melting capacity in terms of kilogram of brass for 'A' shape, spouted tilting type and top-pour type crucibles and in terms of kilogram of aluminium for basin type and spouted basin type crucibles. For example, designation A6 indicates a 'A' shaped crucible having melting capacity of 6 Kg of brass.

The designation number for each crucible shall consist of not more that three letters, indicating the type of crucible followed by a number indicating its nominal melting capacity in terms of kilogram of brass for 'A' shape, spouted tilting type and top-pour type crucibles and in terms of kilogram of aluminium for basin type and spouted basin type crucibles. For example, designation A6 indicates a 'A' shaped crucible having melting capacity of 6 Kg of brass.