Vitrinite fine structure

Figure 3. A band of exinite showing fine structure. The associated vitrinite is almost entirely homogeneous. X 4725...

It was considered likely that any fine structure present might not be obvious owing to lack of contrast. In an attempt to reveal any structures present, samples of vitrinite were evacuated at 10" mm. Hg for several days and then impregnated with a saturated aqueous solution of lead acetate. The solution was allowed to dry over a period of several days and then some of the vitrinite was freed from the encrusting lead acetate, crushed finely, and dispersed on a carbon-collodion filmed grid. 

Figure 2. The ESR absorption of a vitrinite maceral sample from PSOC 297 illustrates the broad, fine structure free character of these spectra.

The physical or petrographic components of coal are defined or described in various ways. In one system, which depends on microscopic observation, the principal components are called exinite, vitrinite, micrinite, and fusinite. Transparency of these in a thin section decreases in that order, whereas reflectance from polished surface increases in the same order. Vitrinite, the major component of most coals, occurs in bands or strands and is usually uniform in appearance, though sometimes shows cell structure exinite consists of the remains of plant spores, pollen, and cuticles with characteristic shape micrinite occurs in very fine granular form or massive structureless, irregular form fusinite shows characteristic fibrous, cellular structure. Semifusinite is transitional between vitrinite and fusinite. On a macroscopic scale, vitrain and... 

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