Copper

Object/Artifact

-

Crater Rock Museum

Name/Title

Copper

Entry/Object ID

2014.1.51

Description

Chemical Composition: Al(OH)3 Crystal System: Hexagonal System Description: Common Name:Copper Chemistry: Cu Group: Element Location: Keweenaw Peninsula, Michigan Description: Specimen is a nearly pure copper nugget. Color is copper! Physical Charateristics: Color is copper colored with weathered specimens tarnished green. • Luster is metallic. • Transparency is opaque. • Crystal System is isometric; 4/m bar 3 2/m • Crystal Habits include massive, wires and arborescent or branching forms as the most common, whole individual crystals are extremely rare but when present are usually cubes and octahedrons. Occasionally, massive forms will show some recognizable crystal faces on outer surfaces. • Cleavage is absent. • Fracture is jagged. • Streak is reddish copper color. • Hardness is 2.5-3 • Specific Gravity is 8.9+ (above average for metallic) • Associated Minerals are silver, calcite, malachite and other secondary copper minerals. Other Characteristics: ductile, malleable and sectile, meaning it can be pounded into other shapes, stretched into a wire and cut into slices. • Notable Occurrences include Michigan and Arizona, USA; Germany; Russia and Australia. • Best Field Indicators are color, ductility and crystal habit. Hardness: 7 Quartz Rock Type: Sedimentary

Collection

RAGM Mineral Collection

Acquisition

Accession

2014.1

Source or Donor

Crater Rock Museum (unknown donors)

Acquisition Method

Gift

Dimensions

Height

3-11/16 in

Width

2-1/4 in

Depth

1-3/4 in

Location

Location

Display Case

FS-11

Room

Frieda Smith Hall

Building

Crater Rock Museum

Category

Permanent

Moved By

Curtis Gardner

Date

December 27, 2023