Name/Title
Limb CastEntry/Object ID
2008.1.18Description
Assemblage Zone: Subtropical Forest
Chemical Composition: Si O2
Crystal System: Hexagonal
Description: Limb Cast (Clock)
Common Name: Limb cast
Age: Eocene
Location data: Hampton Butte, Oregon USA
Description: Polished slice of a limb cast made into a clock, colors greenish swrill with clear
Size: 11.5" X 8.5" width 2/3"
Type of Fossils Present: Plants
Grain Size: Fine
Hardness: 7 Quartz
Lithofacies: Volcaniclastic
Luster: Glassy
Occurrence: Like petrified wood, limb cast are created in much the same manner. Volcanic ash or silica-rich sediment buries a tree limb, the limb decays, leaving behind an open void. This void works as a mold that fills with amorphous silica that has percolated through the surrounding rock. Once microamorphous silica has filled the mold and the crystallization process to a (quartz)chalcedony or opal is complete, the result is a siliceous rock with the same exterior markings as the original limb.
Pressure: Low-Moderate
Rock Color: Medium
Rock Origin: Marine/Freshwater
Rock Type: Sedimentary
Specific Gravity: 2.6
Surface Process: Not apparent
Temperature: Low to moderate
Texture: microcrystaline
Variety: Petrified woods here are hydrous microcrystalline variety of quartz that can be generally termed as chalcedony or opal.Collection
Oren Kellenbeck CollectionAcquisition
Accession
2008.1Source or Donor
Oren Kellenbeck CollectionAcquisition Method
GiftOther Names and Numbers
Other Number
Other Number: 2008.1.18Dimensions
Dimension Notes
Dimension taken at widest pointsLocation
Location
Container
LeftDrawer
2nd shelfShelf
Left side, Left sideWall
Northeast wallRoom
Main Room, Mentzer HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Wendy MondryDate
February 11, 2010Location
Cabinet
ToteBuilding
Storage (old gift shop upstairs)Category
Permanent
