Material | $\varepsilon_r$
-------- | --------------
Dry air | 1.0006
Paper | 3
Diamond | 5
Silicon | 12
HfO $_2$ (Hf = Hafnium) | 25
H $_2$ O | 80
BaTiO $_3$ (Barium Titan - useful for keeping its polarisation) | $\sim 4000$
| Material | \varepsilon_r |
|---|---|
| Dry air | 1.0006 |
| Paper | 3 |
| Diamond | 5 |
| Silicon | 12 |
| HfO _2 (Hf = Hafnium) | 25 |
| H _2 O | 80 |
| BaTiO _3 (Barium Titan - useful for keeping its polarisation) | \sim 4000 |