Do you know what element is hiding in brass?
Or what material is laying low in the ore known as sphalerite?
Or what periodic table member lurks undetected in the wood preservative and insecticide called koettigite?
Or what industrial compound component helps fight dandruff secretly in the form of zinc* pyrithione?
Double agent playing the phosphates against the citrates.
Undercover element extraordinaire.
"Bond. Covalent Bond."
* That one may have given it away.