while the second part is true about mold, so is the first part. I've found that that's the textbook answer cigar shop employees give when a customer finds mold.It looks like mold to me. the Experts at my local B&M (I trust them very much) say the easiest simple test is to just wip them with you fingers. If it comes of easily then its generally plume. If it doesn't come off or it comes off but leaves a mark or stain behind, then its mold. the kicker is it being in the foot. Thats usually a sign of mold.