Borax isnt a preservative, its more of a "bug Proofer" than anything, if they are in a zip lock bag they will not dry and if all the meat and fat isnt all off it will rot and stink. You can get a preservative powder throughany taxidermy supply comany, salt will pull out all the bacteria and moisture on your hides, should do thesame on those claws. Bears are really greasy animals so maybe try cleaning then in some cold water anddawn dish soap.