These are the results of a detailed elemental composition analysis of a sedimentary clay. The first column of numbers is ppm (parts per million), divide them by 10,000 to get percent. The Fe here, for example, is 50,868 or 5.1%. The second column is +/- error. Notice that this test does not detect boron or lithium, they require a different method. By contrast, the chemical analysis shown on the data sheet of a typical ceramic material shows only the principle ceramic oxides (less than a dozen), but all of these trace elements will still be present.
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