Ammonium Magnesium Phosphate Crystals

Radiating stars and crosses form first, such as the one shown here. A little later rectangular crystals with a "trussed roof" structure appear.

Transmitted Oblique Off Crossed Circular Polarized Light

Definition/Function:

This is a standard micro-chemical test for magnesium using sodium phosphate in an ammoniacal solution from the HANDBOOK OF CHEMICAL MICROSCOPY, Vol 2, by Chamot and Mason, pages 130-131. The product formed is NH₄MgPO₄-6H₂O (numbers are subscripts not superscripts).

Significance in the Environment:

Characteristic Features:

Associated Particles:

References:

Chamot, Emile Monnin and Clyde Walter Mason, HANDBOOK OF CHEMICAL MICROSCOPY, Volume II, pp. 130-131, 1940.