Conifer Quarter Cut

Object/Artifact

-

Crater Rock Museum

Name/Title

Conifer "Quarter Cut"

Entry/Object ID

05.58.129

Description

Chemical Composition: Si O2 Crystal System: Hexagonal Description: Family: Not Identified Age: Tertiary Location data: Jackson County, Oregon, USA Description: Horizontal cut slab with distinct grain features, colors white, beige, tan and yellowish-brown **(A Sawyer's View of Wood) On the rght is a "plain-sawed" board cut at a tangent to the tree's growth rings, which show the growth rings as narrow, cone-shaped patterns: most 2'x4's and the other dimensional lumber were plain-sawed. On the left is a "quarter-sawed" board cut through the center of the log, which shows the growth rings as paralled vertical lines and the rays as irregular, interrupted, horizontal lines: quarter-sawed hardwood boards command a high price because of their beautiful pattern. The end of the log, which shows concentric, telescoping growth rings, was cut in cross-section. (ref.Harlow 1970) 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

Petrified Wood Collection

Acquisition

Accession

05.58

Source or Donor

Petrified Wood Collection

Acquisition Method

Donation

Other Names and Numbers

Other Number

Other Number: 2005.58.129

Dimensions

Width

4-1/8 in

Depth

3/4 in

Length

5-3/4 in

Dimension Notes

Dimension taken at widest points

Location

Location

Container

Center

Drawer

Top Shelf

Shelf

Left

Cabinet

Case #101

Wall

South wall

Building

Mentzer Hall - Petrified Wood Room

Category

Permanent