These stamps measure 29 millimeters by 34mm and 30mm by 35mm, respectively, compared to 20mm by 25mm for the stamps shown in Figure 1. Having a consistent size and design for all definitive stamps does have its aesthetic appeal, which is perhaps some consolation for discontinuing a practice that goes back more than 100 years. These two high-value stamps typify the larger size used for British high values from 1867 until this year. On the right is a large intaglio-printed Machin from 1969. However, there may be a second, unstated reason.
Smaller stamps are less expensive to print than larger ones.
These new stamps also do not include the optically variable ink that was used for the small queen's head on the Castle stamps. The use of that ink was an anti-counterfeiting measure. Regardless of the reason, the high values are now small in size and will undoubtedly remain that way for several years. The new stamps do differ from the low values in one important way. They are printed using intaglio, a recess process that starts with a hand-engraved image.