My watch list  


Amygdules form when the vesicular cavities (created by expanding gas bubbles in volcanic lava) are filled with a secondary mineral such as calcite, quartz, chlorite or one of the zeolites, which are deposited by having minerals "wash" through the pores in the rock (see Porosity/Permeability). They are filled from the outside, making some amygdules concentrically layered.

"Amygdules" refer to the smaller ones. "Amygdales" refer to the larger ones and is more common in British usage.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Amygdule". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE