"Frosty", as we'll call him, is a Hemingray CD 155 that was sandblasted, presumably as a novelty. We ran across him in a box with some other (unaltered) common insulators.

This insulator does not appear to have spent any time underground; It is in mint condition. It is frosted evenly, inside and out. The embossing is very crisp.

More information about sandblasting is available here: http://www.insulators.info/books/fake/section3.htm

Scroll down the page to the section entitled "Sandblasted Specimens".