Graddfa Mohs
Graddfa i fesur caledwch mwynau yw graddfa Mohs a grewyd gan Friedrich Mohs ym 1812.[1]
| Safle ar raddfa Mohs | Mwyn | Fformiwla gemegol | Caledwch absoliwt | Delwedd |
|---|---|---|---|---|
| 1 | Talc | Mg3Si4O10(OH)2 | 1 | 
|
| 2 | Gypswm | CaSO4·2H2O | 3 | 
|
| 3 | Calsit | CaCO3 | 9 | 
|
| 4 | Fflworit | CaF2 | 21 | 
|
| 5 | Apatit | Ca5(PO4)3(OH–,Cl–,F–) | 48 | 
|
| 6 | Orthoclas Ffelsbar | KAlSi3O8 | 72 | 
|
| 7 | Cwarts | SiO2 | 100 | 
|
| 8 | Topas | Al2SiO4(OH–,F–)2 | 200 | 
|
| 9 | Corwndwm | Al2O3 | 400 | 
|
| 10 | Diemwnt | C | 1600 | 
|
Cyfeiriadau
golygu- ↑ Encyclopædia Britannica. 2009. Encyclopædia Britannica Online. "Mohs hardness."
