Object Record
Images
Metadata
Title |
Chalcedony |
Catalog Number |
G-1481 |
Collection |
Geology Permanent Collection |
Source |
Dr. Aug. F. Foreste |
Description |
Chalcedony is amorphus(Loomis). Cryptocrystalline quartz - Silicon dioxide - SiO2. Quote fm card by Dr. Foerste. 44.7 grams. Thin sheet of stony matrix. Most like part of the outside of a geode. Ther is dark grey, opaque chalcedony. The cyrstalization boasts a botryoidal surface. |
Label |
Chalcedony: Chalcedony is a form of cryptocrystalline silica. It occurs when quartz crystals and morganite crystals intergrow in and form a solid mass. It comes in a variety of colors which are the result of metallic impurities (iron, nickel, titanium, copper, etc.) that are present during the crystallization process. Botryoidal: When chalcedony forms, it is able to completely fill out cavities in rocks. This term describes the smooth, "lumpy," round bodies that form on the surface when this happens. |