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 |