Black Locust

Object/Artifact

-

Crater Rock Museum

Name/Title

Black Locust

Entry/Object ID

78.58.276 (a)

Description

Assemblage Zone: Sedimentary Chemical Composition: Si O2 Crystal System: Hexagonal Description: Family: Fabaceae Genus: Robinia Common Name: Black Locust Location Data: Grassy Mountain, Oregon Description: Short limb with grey and tan outer area and a polished face cut. Reddish-brown and burnt yellow towards the center. Some striations in a circular pattern. Size: 2.500"x 2.00"x 2.250" 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 Temperature: Low Texture: Microcrystalline Variety: Petrified woods ar hydrous microcrystalline varieties of quartz that can be generally termed as chalcedony or opalized .

Collection

Petrified Wood Collection

Acquisition

Accession

78.58

Source or Donor

Delmar Smith Petrified Wood Collection

Acquisition Method

Donation

Other Names and Numbers

Other Number

Other Number: 78.58.276 (a)

Dimensions

Width

2 in

Depth

2-1/4 in

Length

2-1/2 in

Dimension Notes

Dimension taken at widest points

Location

Location

Display Case

PW-2

Room

Petrified Wood Room

Building

Crater Rock Museum

Category

Exhibit

Moved By

Jillian Mather Kettley

Notes

Added current location