An emission spectrographic method has been developed that has been found suitable for the determination of iron, silicon, chromium, lead, titanium, zinc, and tin in a concentration range of 0 07-1.0%. The method consists of dissolving the sample in hydrochloric and sulfuric acids and converting it to the sulfate. One percent nickel is added as an internal standard and the sample is mixed with 2 parts of graphite. The procedure is found to have an average coefficient of variation of 5.1% for all determinations and has been found suitable is a rapid production control method for magnesium-aluminum alloys of 65/35 and 50/50 compositions.
Seymour Lader, "Emission Spectrographic Analysis of 65/35 and 50/50 Magnesium-Aluminum Alloys," Appl. Spectrosc. 15, 45-46 (1961)