Basswood

Object/Artifact

-

Crater Rock Museum

Name/Title

Basswood

Entry/Object ID

07.58.39(b)

Description

Chemical Composition: Si O2 Crystal System: Hexagonal Description: Family: Tiliaceae Genus: Tilia Common Name: Basswood Age: Lower Oligocene Location data: Sweethome, Linn County Oregon USA Mehama fm. Description: Outer cast is a pinkish tan with a bark texture, the polished face shows growth rings with colors ranging from beige, pinkish tan, and brown **This basswood limb from Sweethome, Oresgon shows several cresent-shaped pressure cracks caused by the weight of overburden pushing down on the limb before it wes fossilized. Had amorphous silica later re-entered this limb, these cracks most likely would have been filled with quartz.. Size:4.500"x 4.750"x 1.750" Type of Fossils Present: Plants Fracture: conchoidal Grain Size: Fine Hardness: 7 Quartz Lithofacies: Volcanic tuff 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 opalization

Collection

Petrified Wood Collection

Acquisition

Accession

07.58

Source or Donor

Petrified Wood Collection

Acquisition Method

Donation

Other Names and Numbers

Other Number

Other Number: 07.58.39(b)

Dimensions

Width

4-3/4 in

Depth

1-3/4 in

Length

4-1/2 in

Dimension Notes

Dimension taken at widest points

Location

Location

Container

Center

Drawer

3rd Shelf

Shelf

Left

Cabinet

Case #108

Wall

South wall

Building

Mentzer Hall - Petrified Wood Room

Category

Permanent