4. Glossary

Rang; rank

Coal rank is both an indicator of the degree of carbonization of the material. High-rank coal is characterized by a high carbon content (>70% on dry basis) and low-rank coal by a lower carbon content. Various parameters are used to classify coal between high and low rank: the volatile matter index (low = high rank / high = low rank), the carbon content, but also its moisture content and its maximum reflectance power. All these parameters can be found in the United Nations' coal classification tables.

Sample

A sample is made up of the sum of elementary samples collected according to time and space interval rules, in an optimal way on a flow of moving materials to guarantee its representativeness.

Withdrawal; increment

This involves collecting a certain...