This is just and educational update to this thread. Purple is the second most common color of cannabis then green. And, if one was to read pages 92 and 93 of Marijuana Botany R. C. Clarke, that cannabis will finish and cure in oranges, yellows, golds, reds, purple and green.

Here's a couple of nugs of my Purple Kush, and the buds aren't purple (taken early due to bud mold), but the plant is still purple finishing inside. And the last buds I get will have more purple in the bud. Still tasty stuff and has a fruity taste the first coupe of hits.