positive crystal en · NOUN
Meanings
- A doubly refracting crystal in which the index of refraction for the extraordinary ray is greater than for the ordinary ray, and the former is refracted nearer to the axis than the latter, such as quartz and ice; as opposed to negative crystal: one in which this characteristic is reversed, such as Iceland spar or tourmaline.
Forms
| Spelling | Features | Labels | Source |
|---|---|---|---|
| positive crystals | Number=Plur | lexicographic |