Magnesium (Mg) is a shiny reactive metal named for the Magnesia region of Greece, where the ores from which it was isolated were mined, as is the element manganese (Mn). It is extremely flammable, and reaches temperatures over 3000 °F, lending to its use as an ignition source for thermite reaction. Magnesium is also the principal ingredient in sparklers.

Magnesium is useful in many chemical reactions, including those used on this site. It can be easily obtained as part of a firestarter, which also includes a ferrocerium striker rod. These are available at sporting goods stores or Walmart for about $15.