Name/Title
Petrified WoodEntry/Object ID
07.58.76 (B)Description
Chemical Composition: Si O2
Crystal System: Hexagonal
Description: Family: Araucariaceae
Genus: Aravacariotylon
Common Name: Arcacaria
Age: Late Triassic (about 215 million years old)
Location data: Dobell-Patton dig site in Arizona USA
Description: 2 large polished slabs with the face colors ranging from brown, tan, beige, rust and red, outer side is mostly a tanish - beige color. No growth rings are apparent and the outer part of the face appears to be like a medium grain sandstone, while the inner part has the color and the wood appearance
Size: 16.00"x 12.750"x 1.750"
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: Light
Rock Origin: Post-depositional
Rock Type: Sedimentary
Specific Gravity: 2.6
Surface Process: Not apparent
Temperature: Low
Texture: medium grain to a Microcrystalline texture
Variety: Petrified woods ar hydrous microcrystalline varieties of quartz that can be generally termed as chalcedony or opalized .Collection
Petrified Wood CollectionAcquisition
Accession
07.58Source or Donor
Petrified Wood CollectionAcquisition Method
DonationOther Names and Numbers
Other Number
Other Number: 2007.58.76 (B)Dimensions
Width
12-3/4 inDepth
1-3/4 inLength
16 inDimension Notes
Dimension taken at widest pointsLocation
Location
Shelf
bottom right, bottom rightWall
right - southRoom
Wood roomBuilding
Mentzer Hall - Petrified Wood RoomCategory
PermanentMoved By
Catherine BoydDate
March 6, 2008Location
Drawer
LeftShelf
BottomCabinet
Case #104(a)Wall
EastBuilding
Mentzer Hall - Petrified Wood RoomCategory
Permanent