Full Idea
It is natural to say that 'being triangular' and 'being trilateral', though necessarily coextensive, are different properties. But what are distinct are the concepts and meanings. If properties are not meanings of predicates, these are identical.
Gist of Idea
Triangular and trilateral are coextensive, but different concepts; but powers and properties are the same
Source
Sydney Shoemaker (Causality and Properties [1980], §04)
Book Reference
Shoemaker,Sydney: 'Identity, Cause and Mind' [OUP 2003], p.214
A Reaction
A good test example. Being renate (kidney) and being cordate (heart) are different, because being cordate produces a thumping noise. Shoemaker's example is pretty much Phosphorus/Hesperus.