No, Cetaphyll is a dermatologist recommended skin cream for folks with severely dry skin, and conditions that can cause it. There's no perfumes, dyes, nothing that triggers allergies. So I figured there wouldn't be anything in it that screws up heavy leather, sheathes, jackets...it really does a bang up job on the new raw leather sheathes like BLACKJACK uses. Go easy, don't overdo it. I've also considered using it as a base carrier for leather dyes, no alcohol. I just put 3 thin coats on the bare raw leather to soften it a bit and darken it. After I got through with the stuff I listed above, the sheath has an old chocolate brown ball glove look. No rotten stitching, not greasy, no cracking. Old Vietnam Randal era look. Wrapped some hunter green paracord. That Blackjack HALO ain't a Randal, but it is convex ground A2, sharp as a razor, easy to maintain and I didn't have to spend $700. I'd love to have the Randal 14 with the 8 inch blade, but this'll do until....