cannel coal is a tough, massive rock with a dull to waxy luster and conchoidal fracture, with bulk density of 1.5 -1.2.

black shale has earthy luster,

thin laminations and fissility, and bulk density of 1.9 or more.

Thanks Ronald.

Can you tell me the cause of Inertinites having high reflectance?

Please find enclosed the definition of "cannel coal" and "black shale" according to the Glossary of Geology, Second Edition by Robert L. Bates and Julia A. Jackson, Editors (1980), American Geological Institute, Falls Church, Virginia 1980.

Quotation:

"cannel coal

A compact, tough sapropelitic coal that consists dominantly of spores and is characterized by dull to waxy luster, conchoidal fracture, and Massiveness. It is attrital and high in volatiles; by American standards it must contain less than 5% anthraxylon. Cf: boghead coal; torbanite. Syn: candle coal, kennel coal; cannel; parror coal; curly cannel. Adj: canneloid."

"black shale

(a) A dark, thinly laminated carbonaceous shale, exceptionally rich in organic matter (5% or more carbon content) and sulfide (esp. iron sulfide, usually pyrite), and often containing unusual concentration of certain trace elements (U, V, Cu, Ni). It is formed by partial anaerobic decay of buried organic matter in a quiet-water, reducing environment (such as in a stagnant marine basin) characterized by restricted circulation and very slow deposition of clastic material. Fossil organisms (principally planktonic and nektonic forms) are preserved as a graphitic or carbonaceous film or as pyrite replacements. Syn: biopelite.

(b) A finely laminated, sometimes canneloid, carbonaceous shale often found as a roof to coal seam (Tomkeieff, 1954, p. 29). Syn: black metal."

Dear Guenter,

Thanks for the reply. I was rather curious about how to differentiate them in hand specimens. I feel Ronald's answer above is more of what I was looking for.

Dear Gangadhar,

Sorry for giving you a misleading answer!

It's okay sir, you're just trying to help. Thanks to you I learnt a bit more..