Zinc Metatungstate, ZnW₄O₁₃

Zinc Metatungstate, ZnW₄O₁₃.10H₂O, is obtained by the addition of zinc sulphate to a solution of the barium salt. It forms readily soluble crystals, according to Wyrouboff monoclinic prisms, with

a:b:c = 1.6626:1:0.7557; β = 105° 57'.

If the salt is crystallised between 6° C. and 20° C. it contains only 8H₂O.