Coal rank

Abbreviation

% Carbon

% Hydrogen

% Oxygen

Lignite

BNK

70

6

34

Sub-bituminous coal

FLK

75

6

>9.8

Gas flame coal*

WBF

84

6.23

7.6

Gas flame coal

WBS

84

6.23

7.6

Fat coal

SEC

88

4.5

2.8

Anthracite

-

94

3

2