Also for the Knoop scale the values of hardness are absolute, and they depend on the depth of the signs engraved on the mineral one from a special utensil with point of diamond, with which a force standard is practiced Mohs Rosiwal and Knoop scale mineral MOHS ROSIWAL KNOOP talc or graphite 1 0.03 1 gypsum or sulfur 2 1.25 32 calcite 3 4.5 135 fluorite 4 5 163 
(the values of hardness; are; absolute) (they; depend; on the depth of the signs) (the signs; engraved; L:on the mineral) (a force standard; is practiced; T:Mohs Rosiwal and Knoop scale mineral MOHS ROSIWAL KNOOP talc) (a force standard; graphite; )
the values of hardness they the signs a force standard a force standard
are depend engraved is practiced graphite
absolute
on the depth of the signs
L:on the mineral
T:Mohs Rosiwal and Knoop scale mineral MOHS ROSIWAL KNOOP talc