it has a very distinct pink with a blue-ish purple on the base I can't describe. The eyes on the MM are basically yellow / gold and the edge is a bright green.
It's hands down one of the best known named corals in the hobby, and after the huge influx of watermelon type chalices a lot of less scrupulous people flooded the market with way more MM's then I know are out there. Us original owners actually had a pact to never sell the coral with a few exceptions. And it's rate of growth from those tiny frags... I just don't see how some many people can have a true lineage MM.
Now, I can't say for fact either way it is or isnt. I can just tell you I've owned several different watermelons before they became common including the MM. It has a color combination that is just so perfect that it kinda just gives itself away, you know when you see it. Not to mention I always remember it being 4 distinct colors; pink, blue, green, and the yellow/green of the eyes. Most other 'melons are only 3 colors. But if you really REALLY want to know you will have to trace it's lineage. If you do decide to do that I can help once you've tracked it back to San Diego, but that's about it.