Powdered samples were sent to the lab. The numbers shown on this report are in percentage-by-weight. That means, for example, that 15.21% of the weight of the dry powder of Alberta Slip is Al2O3. Insight-live knows material chemistries in this way (whereas desktop Insight needs them as formulas). Some non-oxide elements are quantified as parts-per-million (these amounts are not normally high enough to take into account for traditional ceramic purposes). The LOI column shows how much mechanically and chemically bound water are gassed off during firing of the sample. The total is not exactly 100 because of inherent error in the method and compounds not included in the report.
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