Ammonium Dichromate, Grade: Commercial, Purity: 99%

Ammonium dichromate is an inorganic compound with the formula (NH4)2Cr2O7. In this compound, as in all chromates and dichromates, chromium is in a +6 oxidation state, commonly known as hexavalent chromium. It is a salt consisting of ammonium ions and dichromate ions.
Ammonium dichromate is sometimes known as Vesuvian Fire, because of its use in demonstrations of tabletop "volcanoes".[2] However, this demonstration has become unpopular in schools due to the compound's carcinogenic nature. It has also been used in pyrotechnics and in the early days of photography.