GFS has extensive experience manufacturing and sourcing a wide range of rare earth starting materials making us the supplier of choice for your production operations or laboratory use. Although specializing in Cerium III and Cerium IV, we cover the majority of the Lanthanide series by offering several rare earths ranging from ACS reagent grade through 99.99+% purity. GFS is best known for manufacturing the highest quality materials in the 99.9+% metals basis assay (ultra dry and ultra pure).