lithophysa
1Lithophysa — A lithophysa (plural lithophysae) is a small cavity found in felsic volcanic rocks believed to be caused by expanding gases in tuffs before solidification. If it has become lined with crystals it may be referred to as a geode or a thunderegg. The …
2lithophysa — lith·o·phy·sa …
3lithophysa — …
4Geode — For other uses, see Geode (disambiguation). Geode, halved and polished …
5lithophysal — adjective see lithophysa …