Preparation of magnesium nitride
An iron crucible is weight together with the cover and packed fully with 10 g of powdered magnesium by tapping the crucible on the desk to make the powder settle. The crucible is covered tightly and placed on the triangle with a cylinder of asbestos so as to diminish the loss of heat by radiation. The crucible is heated as hot as possible with a Bunsen burner for 45 minutes. After it cools the content of crucible is poured to a piece of paper and the white magnesium oxide on top and the yellow magnesium nitride beneath are gently separated. Magnesium nitride is preserved in a well-stoppered bottle.
Synthetic inorganic chemistry, by A. A. Blanchard, 154-155, 1936