Spheroidal, ellipsoidal, or (literally) ‘almond-shaped’ cavity or vesicle within a lava, filled with secondary minerals, e.g. calcite, quartz, or zeolites.
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。