The synthesis and certification of in-house monazite sand certified reference materials (CRM)

The synthesis and certification of CRM of monazite sand by ISO 13528-2008 and ISO 35-2006 have been done. CRM of monazite sand is necessary to support the determination of the rare earth element composition in the mining materials. The synthesis and certification of monazite sand CRM are done by using monazite sand from Bangka. Monazite sand is dried at 110° C, crushed and sieved until the powder is obtained with the grain size of 200 mesh. The monazite sand powder is homogenized, then water content tested, homogeneous test, stabilization test and characterization test are conducted. Certificate of parameter test results in the CRM monazite sand from 7 accredited laboratories. In the evaluation of data obtained that CRM monazite sand candidate has been homogeneous, stable, and water content<1%. So the monazite sand powder is already qualified physically as CRM. The CRM monazite sand contains chemical compounds cadmium cerium phosphate Cd0.5Ce2(PO4)3, monazite-Ce (Ce, La, Th, Nd)PO4, silica SiO2, titanium sulfide TiS, monazite (Ce, La, Y, Th)PO4 and cerium phosphate CePO4. The certificate of parameter test results in CRM monazite sand from 7 accredited laboratories with ISO 35-2006 statistical methods obtained 20 oxides, among others CeO2 (31.506±0.075)%, La2O3 (13.165±0.038)%, Nd2O3 (11.025±0.062)%, Y2O3 (3.931±0.024)%, ThO2 (6.283±0.022)%, etc. Compared with Myanmar monazite and Egyptian monazite, CeO2, La2O3, Y2O3, Pr6O11 concentrations in the Indonesia monazite sand CRM from Bangka are higher. CRM of monazite sand can be used as the standard material on the composition of rare earth elements determination in the mining result.