Thallous oxalate, Tl₂C₂O₄

Thallous oxalate, Tl₂C₂O₄, prepared from thallous carbonate and oxalic acid, crystallises from boiling water, in which it is not very soluble, in small, pearly, monoclinic prisms (a:b:c = 1.1384:1:2.2405; β = 99°13') of density 6.31. One litre of a saturated aqueous solution of the salt contains 15.77 grams of the oxalate at 20°, and 18.69 at 25°.