Well, pure silkies usually have all the features a silkie should have.
Like walnut comb, black skin, beard, or no beard, 5 toes, & silkied feathers. It is possible for pure silkies to have a few solid feathers, usually in the tail, & wings. But tail should be fully silkied. Wings are usually...
I have a silkie rooster, with horns on the back of his comb. Just considered a flaw if you're showing.
The original non modified walnut has horns, & ridges.