Hackberry

Object/Artifact

-

Crater Rock Museum

Name/Title

Hackberry

Entry/Object ID

05.58.136

Description

Assemblage Zone: Sedimentary Chemical Composition: Si O2 Crystal System: Hexagonal Description: Family: Ulmaceae Genus: Celtis Common name: Hackberry Age: Miocene Location data: Swartz Canyon, Crook County, Oregon Formation: Picture Gorge Description: Thin slab with polished face. Face is black overall with tan and yellow streaks coming from the center outwards. 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: 05.58.136

Dimensions

Width

11 in

Depth

1 in

Length

11-1/2 in

Dimension Notes

Dimension taken at widest points

Location

Location

Display Case

PW-1

Room

Petrified Wood Room

Building

Crater Rock Museum

Category

Exhibit

Moved By

Jillian Mather Kettley

Date

January 14, 2025

Notes

Inventory/Locating