publication_number US 2014011662 A1 abstract methods for producing substantially single phase yttrium phosphate which exhibits the xenotime crystal structure are disclosed the methods can be practiced without the use of high temperatures the resulting yttrium phosphate can be in the form of particles which comprise interwoven strands of crystals of yttrium phosphate and or nanoparticles prepared from such particles application_number US 201313845484 A description the first step in the process of the invention for producing commercial amounts of yttrium phosphate is the formation of a slurry containing a yttrium compound any solid yttrium compound that is relatively insoluble in water can be used typically the yttrium compound will have a solubility less than about 0 1 grams liter examples of yttrium compounds that can be used include yttrium oxide yttrium carbonate yttrium bicarbonate and hydroxide generally enough of the solid yttrium compound is mixed with water so that the resultant slurry contains between about 0 5 and 50 weight percent solids preferably between about 3 0 and about 20 weight percent and more preferably between about 5 and 15 weight percent while the aqueous slurry of the yttrium compound is vigorously agitated phosphoric acid is added to form yttrium phosphate it has been found that using a stoichiometric amount of phosphoric acid results in the formation of yttrium phosphate containing unreacted yttrium compound and unreacted phosphoric acid as well as non xenotime yttrium phosphate it is theorized that this contaminated yttrium phosphate results from an incomplete reaction due to the encapsulation of unreacted.