Salva silver nitrate pencil

Remove the white protective cap and attach it to the other end of the blue bracket,
before use, moisten the tip of the stone with a drop of water, remove excess water by gently shaking on a tissue or disposable paper towel and being careful not to drop any drops, discard the tissue immediately in the trash and
wipe the stone well after use with a disposable tissue.

Silver nitrate 63.3%.
Potassium nitrate 36.7%.