SiO₂ - Mohs Hardness: 6½ - 7. The formation of Agate is most often from deposition of layers of silica filling voids in volcanic vesicles or other cavities. The layers form in stages with some of new layers providing an alternating color. Since the cavities are irregularly and uniquely shaped, each Agate forms its own pattern based on the original cavity shape. When a cavity is completely filled, it forms a solid mass of Agate, but often it is only partially filled, leaving a hollow void which often has crystalline Quartz growths on its innermost layer.
Ruth Jacobs Collection
[no location in description]
The University of Toledo
Digital Initiatives, University of Toledo Libraries
environmental sciences; virtual exhibitions
No Copyright - United States. URI: http://rightsstatements.org/vocab/NoC-US/1.0/
The organization that has made the Item available believes that the Item is in the Public Domain under the laws of the United States, but a determination was not made as to its copyright status under the copyright laws of other countries. The Item may not be in the Public Domain under the laws of other countries. Please refer to the organization that has made the Item available for more information.