Name/Title
LepidoliteEntry/Object ID
2009.62.116Description
Chemical Composition: KLi2Al(Al, Si)3O10(F, OH)
Crystal System: Monoclinic System
Description: Common Name: Lepidolite
Chemistry: KLi2Al(Al, Si)3O10(F, OH)2, Potassium lithium aluminum silicate hydroxide fluoride
Group: Micas
Location: Minas Gerais, Brazil
Description: Thin uniform layers of lavender and silver mineral with a lusterous sheen.
PHYSICAL CHARACTERISTICS:
Color is violet to pale pink or white and rarely gray or yellow.
Luster is vitreous to pearly.
Transparency crystals are transparent to translucent.
Crystal System is monoclinic; 2/m
Crystal Habits include tabular to prismatic crystals with a prominant pinacoid termination. Lepidolite's four prism faces and two pinacoid faces form pseudo-hexagonal crystal "books". The sides of the crystal often tend to tapper. Also as micaseous, lamellar or granular rock forming masses.
Cleavage is perfect in one direction producing thin sheets or flakes.
Fracture is not readily observed due to cleavage but is uneven.
Hardness is 2.5.
Specific Gravity is approximately 2.8+ (average)
Streak is white.
Associated Minerals are quartz, feldspars, spodumene, ambygonite and tourmaline especially elbaite.
Other Characteristics: cleavage sheets are flexible and elastic, meaning they can be bent and will flex back to original shape. Also some specimens may show triboluminescence.
Best Field Indicators are crystal habit, color, cleavage, elastic sheets and associations.
Fracture: uneven
Hardness: 2 Gypsum
Luster: Vitreous
Occurrence: It occurs in granite pegmatites, in some high-temperature quartz veins, greisens, and granites.
Rock Type: Igneous
Specific Gravity: 2.8
Streak: white
Variety: Lepidolite is an uncommon mica and has only in the past decade become available on the mineral market in large quantities. Lepidolite is an ore of lithium and forms in granitic masses that contain a substantial amount of lithium. The lithium content in lepidolite does vary greatly however and low lithium lepidolite is nearly useless as an ore of lithium. The typical violet to pink color of lepidolite is characteristic and is the only field test available to identify lepidolite from other micas. Pink muscovite or very pale lepidolite may confuse an identificationCollection
RAGM Mineral CollectionAcquisition
Accession
2009.62Source or Donor
Museum Collection of MineralsAcquisition Method
DonationDimensions
Width
3 inDepth
4-1/4 inLength
4-1/2 inWeight
0.66 ozLocation
Location
Display Case
FS-6Room
Frieda Smith HallBuilding
Crater Rock MuseumDate
January 3, 2024Location
Container
CenterDrawer
Top shelfShelf
Left, LeftWall
West wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Steve MillerDate
January 26, 2010Location
Drawer
unknown nameShelf
top left shelf, top left shelfWall
West wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Scott LonganDate
September 26, 2009Location
Container
CenterDrawer
Top ShelfShelf
LeftCabinet
Case# 30Wall
EastBuilding
Freida Smith HallCategory
Permanent