The blanks are then passed to an edge rolling machine, by which they are thickened at the edge so as to form a rim to protect the finished coin from wear.
In the case of very large silver coins only one blank is cut in the width of the fillet, but bronze fillets are made wider so that three penny blanks are cut out at each stroke of the machine.
The blanks are converted into coin by receiving an impression from engraved dies.
The blanks are placed in the slide J and the lowest one is carried forward to the die in two successive movements of the " layer-on " K, a rod working backwards and forwards on a horizontal plate and actuating the finger L, fig.
In most foreign mints the blanks are weighed by the automatic balances before being struck, and those which are too heavy are reduced by filing or planing.