Name/Title
Arsenopyrite on SphaleriteEntry/Object ID
78.62.233Description
Chemical Composition: CuFeS2
Crystal System: Tetragonal System
Description: Common Name: Chalcopyrite
Chemistry:CuFeS2
Class: Sulfides
Location: Joplin,Missouri
Description: A large piece of Chalcopyrite and Zinc Pyrite ore from Joplin,Missouri. Delmar says it's his best piece from this area as for the intensity of color. Colors: Metalic grey triangular crystals of Sphalerite metalic gold Pyrite and Chalcopyrite,all with a rainbw sheen.
PHYSICAL CHARACTERISTICS:
• Color is brassy yellow, tarnishes to irredescent blues, greens, yellows and purples.
• Luster is metallic.
• Transparency: Crystals are opaque.
• Crystal System is tetragonal; bar 4 2m
• Crystal Habits are predominantly the disphenoid which is like two opposing wedges and resembles a tetrahedron. Crystals sometines twinned. Also commonly massive, and sometimes botryoidal.
• Cleavage is rather poor in one direction.
• Fracture is conchoidal and brittle.
• Hardness is 3.5-4
• Specific Gravity is approximately 4.2 (average for metallic minerals)
• Streak is dark green.
• Other Characteristics: Some striations on most crystal faces.
• Associated Minerals are quartz, fluorite, barite, dolomite, calcite, pentlandite, pyrite and other sulfides.
• Notable Occurances include Chile, Peru, Mexico, Europe, South Africa, several USA sites and many others around the world.
• Best Field Indicators are crystal habit, tarnish, softness and brittleness.
Fracture: conchoidal
Grain Size: Fine
Hardness: 4 Fluorite
Luster: Metallic
Pressure: Moderate
Rock Color: Dark
Rock Origin: Post-depositional
Rock Type: Sedimentary
Specific Gravity: 4.2
Streak: Dark green
Temperature: Moderate to highCollection
Delmar Smith Mineral CollectionDimensions
Width
5-1/4 inDepth
3 inLength
6-1/2 inDimension Notes
Dimension taken at widest pointsLocation
Location
Display Case
FS-5-ARoom
Frieda Smith HallBuilding
Crater Rock MuseumCategory
ExhibitMoved By
Ian C.Date
January 29, 2025Notes
Major mineral groups installationLocation
Shelf
CS-F-7Room
Curation StorageBuilding
Crater Rock MuseumCategory
StorageMoved By
CuratorDate
February 16, 2024
