Fur: Real/Fake

I've seen some mentions here and there about various brands/offbrands using real fur versus using fake fur- but I'd like to know if there's any sort of list or definitive information on which brands use what. I know personally I starkly prefer one option over the other, so I'd like to know what I'm getting if I was to purchase something with any fur on it and HelloLace/Lolilibrary don't always list what the fur is.