The Rainbow was a short-lived series in the early? 1980s. I've sometimes wondered if the Midnight began as a Rainbow series. The Aztec has a sparkly gilt-like painted metallic finish in a bronze-orange tone, with "sun gold" lava in clear liquid. Another unknown-named model has the same painted finish in metallic red, and a darker orange lava has been seen, similar to the rare "pumpkin" color sold with Midnights in the late 80s.