Nails are on the hands, fingers of legs. Paronichia.

Fungus pyri.
And if nails covered with scabs,thus take pear sponge as a size,like nail, damaged with scabs and put her in bull gall, not in cow ball, after sponge put on nail damage for 9 days and 9 nights. And if applied on the nail sponge is dried,again wet in gall, after a hurt nail will fallen and will new grow a healthy.
As a cold and humidity of sponge with force and acid of bulls acid , not a cow,thus she better keep temperature,remove a nail peeling,as a humidity for spomge is not endures a scab, and thus cures a damage nail.

As maybe this method you can use for a remove a chronic nail abscess as a finger of feet, as here an acid of gall bull is a object for a study of anti fungus effect.

Abscess of nail bed, wounds healing, ulcers on shins and knees.
Emerald.
Stones germ cure.
As if are microbes and pathogenic bacterias covered your nails,thus need apply a flax fabric on the ulcer and put on the top a stone and bandage and wrap a still layers of flax fabric till conus receiving as a method for natural curing. A stone take a warm within a three days or more times and filled worms will died.