Potassium Uranyl Acetate
These lath crystals form if potassium is present in a
powder added to a uranyl acetate
solution.
Transmitted Circular Polarized Light
Definition/Function:
These are characteristic crystals of K(C2H3O2)-A
standard test for potassium is to test
the dry salt with a solution of uranyl acetate
(UO2(C2H3O2)-2H2O)
in water made acid with a little acetic acid. If potassium ions are present well in
excess of any divalent
ions then these typical crystals are evident. If these crystals form then potassium is
present.
If these crystals don't form then potassium ions are not present or they are part of a
complex
crystal structure that may not be unique. Extraction of the interfering elements may be
required.
Significance in the Environment:
Characteristic Features:
Potassium Uranyl acetate has a relatively high refractive index and is birefringent.
Associated Particles:
A number of other crystalline or non-crystalline phases may be present. A summary of the
elements that may cause these
other precipitates is given on page 57 and 58 of Chamot and Mason.
References:
Chamot, Emile Monnin and Clyde Walter Mason, HANDBOOK OF CHEMICAL MICROSCOPY, Volume II,
pp. 51-58, 1940.
