Name/Title
SpruceEntry/Object ID
78.58.101Description
Assemblage Zone: Sedimentary
Chemical Composition: Si O2
Crystal System: Hexagonal
Description: Family: Pinaceae
Genus: Picea
Common name: Spruce
Age: Mid-Miocene
Location data: Cedarville, Modoc County, California
Formation: Warner Mt. Basalt
Description: Complete round, tan on the outside, blue-clear botryoidal agate on uncut face; cut face, black and white after bleaching. Tramatic resin cracks (from frost damage) on several outer growth rings.( per Doug Foster)
Size: 2.250"x 1.500"x 1.500"
Type of Fossils Present: Plants
Fracture: conchoidal
Grain Size: Fine
Hardness: 7 Quartz
Luster: Glassy
Occurrence: Silicified wood, which is the fossilization and opalization of organic woody matter by the deposition of SiO2 in a anaerobic environment to prevent decay. This means that the wood must somehow be buried in an oxygen free enviroment, possibly in the silt-laden river or the bottom of a lake or buried by volcanic ash or related volcanic mudflow. The organic material in the wood is then replaced by silica (SiO2), other minerals determined its colors.
Pressure: Low-Moderate
Rock Color: Medium
Rock Origin: Post-depositional
Rock Type: Sedimentary
Specific Gravity: 2.6
Surface Process: Not apparent
Streak: white
Temperature: Low
Texture: Mircrocrystalline
Variety: Petrified woods here are hydrous microcrystalline variety of quartz that can be generally termed as chalcedony.Collection
Delmar Smith CollectionLocation
Location
Display Case
PW-1Room
Petrified Wood RoomBuilding
Crater Rock MuseumCategory
ExhibitMoved By
Jillian Mather KettleyDate
January 14, 2025Notes
Inventory/Locating
