To build on bjherbison's comments ...
When the first 3 kreuzer is struck in Ferdinand Karl's name in 1638, he is 10 years old.
When the last 3 kreuzer is struck in his name in 1662 he is 34 (and dies the same year).
It was typical for the bust to change as the ruler aged (especially from a child to an adult).
The young bust with the rounder face and broad flat collar was used 1638-1646, and the date is always divided by the bust. It looks like the Moser-Tursky catalog has this as #495,496.
An older bust with a thinner face and less obvious collar was used starting 1646. As seen in the Numista listing, there was a variant where the date ran vertically in a couple of years. Moser-Tursky has the later years as #518, 519.
Numista doesn't always follow KM exactly, and it looks like in this case the decision was to split the KM type based on the change in bust in 1646 as done by M-T.
And yes, also as bjherbison said, variations in the abbreviation of a word were par for the course back then.
When the first 3 kreuzer is struck in Ferdinand Karl's name in 1638, he is 10 years old.
When the last 3 kreuzer is struck in his name in 1662 he is 34 (and dies the same year).
It was typical for the bust to change as the ruler aged (especially from a child to an adult).
The young bust with the rounder face and broad flat collar was used 1638-1646, and the date is always divided by the bust. It looks like the Moser-Tursky catalog has this as #495,496.
An older bust with a thinner face and less obvious collar was used starting 1646. As seen in the Numista listing, there was a variant where the date ran vertically in a couple of years. Moser-Tursky has the later years as #518, 519.
Numista doesn't always follow KM exactly, and it looks like in this case the decision was to split the KM type based on the change in bust in 1646 as done by M-T.
And yes, also as bjherbison said, variations in the abbreviation of a word were par for the course back then.