Size is as-packaged, or the diameter of loose marbles. ("D" is the diameter of round items other than marbles.)
Opaque green cat's-eye with 5 fat vanes. One vane is enveloped in transparent blue. Named by David Chamberlain. Very rare cat's-eye. Only several hundred known from Long Island find. Identified as a Marble King by Larry Castle, co-author of the Cat's-Eye ID Guide.