re:But it really doesn't look like either ice or frost.

maybe not to much like ice, which during ice storms is often a clear glace, but like frost, it does too!

frost can be thick and textured, and almost pure white, and most definately on the opaque end of translucent! Lucky you if you don't often get a hard frost.. and i suspect Wow, or Bean or Bel all regualarly get thicker frosts than i do!