643.5 Mohs = 6.31 HRC
| Mohs | HRC |
|---|---|
| 628.5 Mohs | 6.16 |
| 633.5 Mohs | 6.21 |
| 638.5 Mohs | 6.26 |
| 643.5 | 6.31 |
| 648.5 Mohs | 6.36 |
| 653.5 Mohs | 6.41 |
| 658.5 Mohs | 6.46 |
643.5 Mohs = 6.31 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