Name/Title
ElmEntry/Object ID
78.58.225Description
Assemblage Zone: sedimentary
Chemical Composition: Si O2
Crystal System: Hexagonal
Description: Family: Ulmaceae
Genus: Ulmus
Common Name: Elm
Age: Miocene
Location data: Yakima Canyon, Washington
Description: Thick slice of petrified wood. Polished sides show three open holes in center surrounded by orange, beige, brown and black wood with white opalized wood at outer rim along half of piece. Large crack runs through center, other smaller cracks extend inward from outer edge. Growth rings apparent.
Size: 8.00"x 8.00"x 1.00"
Type of Fossils Present: Plants
Fracture: conchoidal
Grain Size: Fine
Hardness: 7 Quartz
Luster: Glassy
Occurrence: Silicified wood, which is the fossilization and/or 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 volcanic related mudflow. The organic material in the wood is then replaced by silica, other minerals determined the colors of the petrified wood.
Pressure: Moderate
Rock Color: Medium
Rock Origin: Post-depositional
Rock Type: Sedimentary
Specific Gravity: 2.6
Surface Process: Not apparent
Streak: white
Temperature: Low
Texture: microcrystalline
Variety: Petrified wood is hydrous microcrystalline variety of quartz that can be defined in general term of chalcedony or opalizationCollection
Petrified Wood CollectionAcquisition
Accession
78.58Source or Donor
Delmar Smith Petrified Wood CollectionAcquisition Method
DonationOther Names and Numbers
Other Number
Other Number: 78.58.225Dimensions
Width
8 inDepth
1 inLength
8 inDimension Notes
Dimension taken at widest pointsLocation
Location
Display Case
PW-3Room
Petrified Wood RoomBuilding
Crater Rock MuseumCategory
ExhibitMoved By
Jillian Mather KettleyDate
February 28, 2025Notes
Installed after rebuild of case 3
