Magnesium Molybdate, MgMoO₄

Magnesium Molybdate, MgMoO₄.7H₂O, is obtained in slender, glancing prisms, which resemble Epsom salts, by crystallisation after heating magnesia with molybdic acid and water. It is unstable in air, easily soluble in water, and dehydrates without melting when heated. The pentahydrate separates from more concentrated solutions; it becomes the dihydrate at 100° C. Some complex molybdates,1 and the double molybdates K₂MoO₄.MgMoO₄.2H₂O and (NH₄)₂MoO₄.MgMoO₄.2H₂O, have been described.

MgMoO₄ occurs naturally as belonesite in colourless, white, tetragonal crystals.