All three types of coins were issued at about the same time, and they were made by one engraver - William Wyon. Can anyone suggest a history of this feature? Or write where you can read. Please!
In the early 1860s the Royal mint did a great deal of modifications to coinage experimenting with border design until they adopted the standard one and it looks like these are a part of that process and it seems they issued them into circulation
There is a version that this is protection against counterfeiting. A peculiar micro-font of the 19th century. But the version has not been confirmed by anything. And I want to get accurate information.