840 Mohs = 8.24 HRC
| Mohs | HRC |
|---|---|
| 825 Mohs | 8.09 |
| 830 Mohs | 8.14 |
| 835 Mohs | 8.19 |
| 840 Mohs | 8.24 |
| 845 Mohs | 8.28 |
| 850 Mohs | 8.33 |
| 855 Mohs | 8.38 |
840 Mohs = 8.24 HRC
1 HRC ≈ 10.2 HV · 1 HRB ≈ 1.8 HV · 1 Mohs ≈ 0.1 HV — approximate; real conversions vary by material per ASTM E140