bituminite is found in oxic to anoxic lacustrine and marine environments commonly associated with other maceral minerals such as alginite and liptodetrinite. the organic material undergoes diagenesis, forming an amorphous matrix. framboidal pyrite is a common feature associated with bituminite. this is caused by bacterial reworking of the digestible organic matter. due to the reworking of organic matter the particles/grains of bituminite often appear diffuse and blurred. though grains of bituminite are often too blurred to distinguish, its optical properties widely vary, and are therefore used to determine the bituminite type.