If you suspect mold, DO NOT SMOKE IT.
All this BS about purple haze too... it's SO old.
Purple weed is purple because genetically it can be, and some strains show purple at normal growing temps, while others require a drop in temps to go purple.
Just a little FYI, the same drop in temps to make a bud purple can also lead to a rise in the %RH and DEWFALL on the buds, yes, even INDOORS... and moisture on a nearly-ripe bud is a BAD risk of mold.
You say purplish-black? That doesn't sound good to me at ALL.
Don't listen to the terrible advice of people saying 'so? I'd smoke it! mold be damned'... since when is getting high worth putting yourself at risk for a respiratory infection? I'd actually consider that a substance abuse problem.
People can be pretty dumb/desperate.