RAW_MATERIAL LENGTH_(mm)
Chert 6.3
Chert 10.5
Flint 10.6
Chert 16.8
Flint 18.9
Chert 20.6
Chert 21.3
Chert 21.8
Chert 22.0
Chert 22.2
Chert 23.8
Chert 25.7
Chert 25.8
Flint 25.9
Chert 33.2
Chert 44.6
Flint 48.3