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You have an extreme angle on the top-half. Below that is a much thinner angular grind, done longitudinally.
The bottom grind is not absolutely 'straight' in most cases I have seen. Some do seem...

The Mappin Bros Lancet-Edged razor falls into the same category as the OP's.

If you consider the angle from the spine-contact to the bevel, The old half-rattlers might seem the same as those...

The old Wosty is what I call a half-rattler. Made before the English got with the (extreme) hollow-ground program.
Seems all the heavy-hitters did them, followed by 'rattlers', which had the...