1) Ammonium mineral 2) Orthorhombic mineral 
Mascagnite is a rare ammonium sulfate mineral (NH4)2SO4. It crystallizes in the orthorhombic system typically forming as stalactitic masses exhibiting good cleavage. It is soft (not higher than 2.5 on the Mohs Scale) and water soluble. Optical properties are variable; the purest form is transparent and colorless, but opaque gray or yellow deposits...
• (n.) Native sulphate of ammonia, found in volcanic districts; -- so named from Mascagni, who discovered it.
Ammonium sulfate