Ron Guth:
The 1887 Dime has the fourht largest mintage of the entire Seated Liberty Dime series, exceeded only by the 1853 With Arrows, 1876, and the 1891. As such, it is an excellent candidate for a type coin because it is plentiful, affordable, and it comes in hgih grade. The best examples appear to be a pair of NGC MS68*'s.
Dime Researcher, Gerry Fortin, has identified seventeen different die varieties for this year, including two Proof-only die pairs. It is highly likely that new varieties will be discovered in the future because of the massive mintage of 1887 Dimes.