adjective
- (of igneous rock) having a fine-grained or glassy texture with crystals too small to be seen with the naked eye
Usage: geology; technical
Examples
- Basalt is an aphanitic rock that cools rapidly at the Earth's surface.
- The geologist identified the specimen as aphanitic due to its smooth, glassy appearance.
- Aphanitic textures form when magma cools too quickly for large crystals to develop.
- Unlike phaneritic granite, aphanitic lava flows have microscopic crystal structures.
- The dark aphanitic rock was likely formed from a volcanic eruption.