1.1 ,This test method describes the determination of sulfated ash content (sometimes called residue-on-ignition) of organic materials by thermogravimetry. This test method converts common metals found in organic materials (such as sodium, potassium, lithium, calcium, magnesium, zinc, and tin) into their sulfate salts permitting estimation of their total content as sulfates or oxides. The range of this test method is from 0.1 to 100 % metal content.