Name/Title
ColemaniteEntry/Object ID
2004.1.140Description
Chemical Composition: CaB3O4(OH)3-H2O
Crystal System: Monoclinic System
Description: Common Name: Colemanite
Group Name:
Chemistry: CaB3O4(OH)3-H2O
Location: Billie Mine, Death Valley, CA
Description:
PHYSICAL CHARACTERISTICS:
Color is white to clear.
Luster is vitreous.
Transparency crystals are transparent to translucent.
Crystal System is monoclinic; 2/m
Crystal Habits are quite variable, but include the short prismatic crystals always with complicated facets. Equant crystals that appear stubby and bead-like are also common. The crystals are sometimes flattened and can appear bladed. The terminations are either blunted or steeply pyramidal. Also massive, lamellar and granular habits are found.
Cleavage is perfect in one direction and distinct in another.
Fracture is uneven.
Hardness is 4.5
Specific Gravity is approximately 2.4 (somewhat lower than average)
Streak is white.
Associated Minerals are calcite, celestite, borax, ulexite, kernite, hydroboracite and other borate minerals.
Other Characteristics: exfoliates (peels off) upon heating.
Best Field Indicators are crystal habit, associations, locality, density, cleavage and hardness.
Fracture: uneven
Hardness: 4 Flourite
Luster: Vitreous
Occurrence: Notable Occurrences include Yermo, Boron, Death Valley and other California localities, USA; Nevada, USA; Chile and Panderma, Turkey.
Colemanite is a borate mineral found in evaporite deposits of alkaline lacustrine environments. Colemanite is a secondary mineral that forms by alteration of borax and ulexite.
Specific Gravity: 2.4
Streak: whiteCollection
Suomynona Mineral CollectionAcquisition
Accession
2004.1Source or Donor
Suomynona Mineral CollectionAcquisition Method
DonationDimensions
Width
2-1/2 inDepth
2 inLength
4-1/2 inDimension Notes
Dimension taken at widest pointsLocation
Location
Room
Neil JohnsonBuilding
Attic StorageCategory
PermanentMoved By
Lehman R.Date
August 28, 2009Location
Container
RightDrawer
Front Row / 2nd ShelShelf
Right, RightWall
NorthBuilding
Founders RoomCategory
PermanentMoved By
Lehman R.Date
August 28, 2009Location
Shelf
RightCabinet
Case # 7Room
Mentzer HallBuilding
Crater Rock MuseumCategory
Permanent
