Which one of the following statements is CORRECT for coal?
Show Hint
- Sapropelic coals are composed of a mixture of macroscopic plant debris
- Fusain is a microlithotype in coal
- Clarain is grey in color and has dull lustre
- High value of vitrinite reflectance indicates a low rank coal
The Correct Option is B
Solution and Explanation
- Sapropelic coals are rich in humic material and formed in low-energy, swampy environments. They do not consist of just macroscopic plant debris, but a combination of plant material and organic matter.
- Fusain is a microlithotype (a distinct part of a coal) that is composed of carbonized plant material. It is known for its dark color and high reflectance.
- Clarain is generally lighter in color and has a dull to shiny lustre, contrary to the statement in option (C).
- High vitrinite reflectance is indicative of high-rank coals, not low-rank coals. High vitrinite reflectance corresponds to coals with high carbon content (higher rank).
Thus, the correct answer is (B) Fusain is a microlithotype in coal.
Final Answer: \[ \boxed{\text{Fusain is a microlithotype in coal}} \]
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