On Grading A Peru 1909/7 Half Dinero

A while back, I bought a group of Peru 1/2 Dinero coins, all in a similar grade to the coin below. Some toning is present, with reflective fields and semi-frosted relief details. At 15mm, it's a small coin. Under a loupe, I see no overt signs of wear/rubbing/hits--a few random nicks, and polishing lines in the fields.

If somebody here collects this series, perhaps you can clue me in to the high points on the design--thanks!

2 shots of the coin, in different lighting





The 7 is clearly visible under the 9. According to Krause, it's the "key" of this series, which has many other nice overdates.