Rock class raiting

Rock class

5

4

3

2

1

Rock subclass

B

A

B

A

B

A

B

A

B

A

R m raiting

0 - 10

11 - 20

21 - 30

31 - 40

41 - 50

51 - 60

61 - 70

71 - 80

81 - 90

91 - 100

Description

Very poor

Poor

Fair

Good

Very good

Color

Red

Brown

Yellow

Green

Blue