This digestion is as total as an acid digestion can get, but will still not dissolve very resistate phases like chromite, barite, monazite, sphene, xenotime, etc. The method is NOT suitable for rare earth elements. This digestion is used for Cu, Ni, Co, Pb, Zn, Mo and Ag assays.
The digestion uses nitric, perchloric, hydrofluoric and hydrochloric acids with temperatures to 260°C. Assay packages for base metals using 4 acid digestions are then analyzed by ICP-OES.
8 – 4-Acid ICP-OES Elements and Detection Limits
Note: Extraction for Total Digestion is dependent on mineralogy.