Limestone vs. Synthetic Sapphire
Limestone belongs to the natural stone classification, while synthetic sapphire belongs to the oxide-based engineering ceramics. There are 17 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.
For each property being compared, the top bar is limestone and the bottom bar is synthetic sapphire.
Metric UnitsUS Customary Units
Mechanical Properties
| Compressive (Crushing) Strength, MPa | 700 | |
| 2700 |
| Elastic (Young's, Tensile) Modulus, GPa | 77 | |
| 450 |
| Poisson's Ratio | 0.25 | |
| 0.28 |
| Shear Modulus, GPa | 30 | |
| 150 |
| Tensile Strength: Ultimate (UTS), MPa | 100 | |
| 2470 |
Thermal Properties
| Maximum Temperature: Mechanical, °C | 360 | |
| 2000 |
| Specific Heat Capacity, J/kg-K | 920 | |
| 760 |
| Thermal Conductivity, W/m-K | 2.1 | |
| 30 |
| Thermal Expansion, µm/m-K | 8.0 | |
| 5.3 |
Electrical Properties
| Dielectric Strength (Breakdown Potential), kV/mm | 8.0 | |
| 9.9 |
Otherwise Unclassified Properties
| Density, g/cm3 | 2.6 | |
| 4.0 |
Common Calculations
| Stiffness to Weight: Axial, points | 16 | |
| 63 |
| Stiffness to Weight: Bending, points | 55 | |
| 64 |
| Strength to Weight: Axial, points | 11 | |
| 170 |
| Strength to Weight: Bending, points | 18 | |
| 100 |
| Thermal Diffusivity, mm2/s | 0.88 | |
| 9.9 |
| Thermal Shock Resistance, points | 12 | |
| 74 |