Vermiculite doesn't contain asbestos these days, even if it's 'insulation' vermiculite.
Because the price of insulation vermiculite is much lower than the price of horticultural vermiculite, I always use the insulation vermiculite ( about $ 25 for 100 liters). Usually the vermiculite I buy is beige, but I had once a darker color. There was no difference in germination at all.
I never used the horticultural vermiculite, but I doubt the germination will be better. It's just a commercial trick to ask more for the same product.
http://seedsite.eu/zaaiinstruc...