everytime I use Neatsfoot oil I get problems with white mold on the leather. I now use Nikwax on my leather cartridge bags and gun cases etc.
I still use Neatsfoot on my leather work boots, only because it is cheap - they still go mouldy! I have heard it said that NF oil rots stitching - this is probably true if it is the old natural fibre cotton threads etc.
It probably goes mouldy as it is from cattle hooves and is at the end of the day a natural "food stuff" oil - and probably goes mouldy just like old food!
