Name/Title
UlexiteEntry/Object ID
2014.1.40Description
Chemical Composition: Al(OH)3
Crystal System: Hexagonal System
Description: Common Name: Ulexite
Chemistry: NaCaB5O6(OH)6-5H2O
Group: Carbonates
Location: California
Description: Small block with flat, smooth surfaces on two sides. Color is creamy white with vertical linear structure.
Physical Charateristics:
Color is white or gray to colorless.
• Luster is silky.
• Transparency crystals are transparent to translucent.
• Crystal System is triclinic; bar 1
• Crystal Habits include tufts of acicular crystals called "cotton balls". Also as vein-like masses of parallel fibrous crystals.
• Cleavage is perfect in one direction.
• Fracture is fibrous.
• Hardness is 2 (softer than a fingernail)
• Specific Gravity is approximately 1.97 (very low density)
• Streak is white.
• Associated Minerals are borax, colemanite, hydroboracite and other borate minerals.
• Other Characteristics: similar borate minerals have an alkaline taste, while ulexite is tasteless.
• Notable Occurrences include several localities in California and Nevada, USA; Tarapaca, Chile and Kazakhstan.
• Best Field Indicators are crystal habit, associations, locality, density, unique optical property, and hardness.
Hardness: 7 Quartz
Rock Type: SedimentaryCollection
RAGM Mineral CollectionAcquisition
Accession
2014.1Source or Donor
Crater Rock Museum (unknown donors)Acquisition Method
GiftDimensions
Height
1-11/16 inWidth
1-3/8 inLength
1-3/8 inLocation
Location
Display Case
FS-11Room
Frieda Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Curtis GardnerDate
December 27, 2023