No.

Material

Porosity (%)

No.

Material

Porosity (%)

1

Coarse gravel

28

13

Coarse sandstone

45

2

Medium gravel

32

14

Loose material

49

3

Gravel

34

15

Peat

92

4

Coarse sand

39

16

Schist

38

5

Medium sand

39

17

Mudstone

35

6

Fine sand

43

18

Claystone

43

7

Mud (silt)

46

19

Shale

6

8

Clay

42

20

Tuff

41

9

Fine grain sandstone

33

21

Basalt

17

10

Medium sandstone

37

22

Weathered gabro

43

11

Limestone

30

23

Weathered granite

45

12

Dolomite

26