The transferring of the die to the plate is accomplished essentially through a process of pounding the design that is on the hard steel transfer roll onto a soft steel plate. In our modern era this is done mechanically, and usually flawlessly. In the classic period of philately (usually defined as lasting from 1840, when the first stamp was printed, until about 1880), transferring was done generally by hand. The extreme pressure that was required to adequately “rock in” the hardened die onto the soft steel produced a number of subtle differences between the stamps. This is because no two stamp impressions on the plate were “rocked in” with the same firmness of all minute portions of the design. Thus, each stamp on the place is subtly different, and because of these minor differences it is usually possible for a stamp specialist to “plate” a particular stamp. “Plating” means identifying the positions of each stamp on the sheet through these minute differences, and the process can be compared to the marking of a jigsaw puzzle.
Plating is highly detailed work, and is held in esteem by serious philatelists. One must have a great deal of time and patience (and no children scurrying around the house upsetting things). Two of the most famous American philatelists, Stanley Ashbrook and Carroll Chase, gained a large measure of their philatelic fame through their plating work. Although it is beyond the scope of this book, most competent stamp dealers are willing to show those interested the basics of plating. From a dealer’s point of view, a plater needs hundreds of the same stamp, so you can be sure he will help you to learn the skill. (This accounts for the relatively high price of certain stamps, such as the United States one cent 1851 which, though issued in abundant quantities, sells for a significantly higher price than certain other stamps from the same period that have not survived in such large numbers. The one cent 1851 is a relatively easy stamp to plate and, as may be expected, the thousands who plate it require a huge supply.)