Victorian brown coal is a family of low-rank coals with unique physical and chemical properties. This chapter deals with petrography of Victorian brown coal, its structure and composition at the macroscopic and microscopic levels when it is examined as an organic rock using optical microscopy at up to 1,000 magnifications. From the petrographic description of Victorian brown coal, it is clear that the brown coal has not undergone extensive coalification that could only take place at elevated temperature and pressure for prolonged time under geological conditions. As a result, the coal seam contains large amounts of water, amounting up to 66% of its mass. The transformation of coal at this stage confers special physical structure and properties to the Victorian brown coal, which contains abundant oxygen-containing functional groups, making the coal hydrophilic. This is the primary reason for its water contents as much as around 65 wt% on a wet basis. Therefore, water is an integral part of the brown coal in its natural status.
All Science Journal Classification (ASJC) codes