| Location | Main Location |
| Location Code | 204 Flammable 1 |
It is a salt consisting of ammonium ions and dichromate ions. sometimes known as Vesuvian Fire, because of its use in demonstrations of tabletop "volcanoes". It has been used in pyrotechnics and in the early days of photography as well as in lithography, as a source of pure nitrogen in the laboratory, and as a catalyst. It is also used as a mordant for dyeing pigments, in manufacturing of alizarin, chrome alum, leather tanning and oil purification