Owner Comments:
I own an AU 50ish 1891 (flat-top) Dinero that I will be sending to NGC in the next batch.
The 1891 Dinero is a series "sleeper" and very scarce to rare in all grades. There are perhaps a few more survivors of this date than the 1892 Dinero.
Flat lists two varieties: A flat-top "1" in the date, and a curved-top "1" with larger numerals. The price guide lists the 1891 at $44 in MS 60, which is well under-valued.
One has been graded in MS 62 at NGC.
Bar one coin, all examples I have seen have a flat-top "1". The "8" is higher than the first "1".
I own a cleaned VF/XF curved-top "1". The first "1" is much higher than the "8", the "9" is higher than the "8", and the last "1" is higher than the "9". All numerals sans the last "1" have strong re-punching. The numerals are a touch larger on the curved-top "1" coin, but the date is not any wider or narrower.