ASH
This sample type includes fly and bottom ash from incineration plants. Ash is often highly heterogeneous. This applies especially to bottom ash. Grinding the sample makes it easier to obtain a representative subsample and improves the reliability of the analytical result. We therefore recommend clients to include grinding when ordering the analysis.

FUSION
After drying at 105°C, samples are fused in a carbon crucible with a flux (in this case lithium metaborate) at 1000°C. The "bead" which forms on cooling is then dissolved in dilute acid. The LOI (Loss On Ignition) is determined by an initial ignition at 1000°C of part of the sample. The resulting weight reduction, LOI, usually reflects the content of organic material in the sample. However, some inorganic components may be driven off during ignition (such as carbon dioxide from carbonates) and contribute to the LOI.