You will get the same reaction out of corn flakes or "iron fortified/fortified" foods and cereals. Its iron. I dont know why it wpuld be in the pill but a secondary test to remove the lettering then dissolve the pill woumd show that the iron is in the pressed powder. To add, Graphene oxide is so tiny of a particle that it wouldnt be that size and would most likely not be visible using the method she used.