Name/Title
LepidoliteEntry/Object ID
2009.62.128Description
Chemical Composition: Hydroxide Fluoride
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: Zambesi Region, Mozambique, Africa
Description: Large cylindrical, scaly, layered, lilac colored crystalline structure with a relatively smooth appearance.
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: none
Hardness: 3 Calcite
Luster: Vitreous
Occurrence: Lepidolite (KLi2Al(Al,Si)3O10(F,OH)2 is a lilac-gray or rose-colored phyllosilicate mineral of the mica group that is a secondary source of lithium.[3] It is associated with other lithium-bearing minerals like spodumene in pegmatite bodies. It is one of the major sources of the rare alkali metals rubidium and caesium.[4] In 1861 Robert Bunsen and Gustav Kirchhoff extracted 150 kg of lepidolite and yielded few grams of rubidium salts for analysis, and therefore discovered the new element rubidium.[5]
It occurs in granite pegmatites, in some high-temperature quartz veins, greisens, and granites. Associated minerals include quartz, feldspar, spodumene, amblygonite, tourmaline, columbite, cassiterite, topaz, and beryl.[1]
Rock Type: Sedimentary
Specific Gravity: 2.8
Streak: whiteCollection
RAGM Mineral CollectionAcquisition
Accession
2009.62Source or Donor
Museum Collection of MineralsAcquisition Method
DonationDimensions
Width
6 inDepth
5-1/4 inLength
14 inWeight
25 ozLocation
Location
Display Case
FS-6Room
Frieda Smith HallBuilding
Crater Rock MuseumDate
January 3, 2024Location
Container
LeftDrawer
Top ShelfShelf
Right, RightWall
West wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Steve MillerDate
January 30, 2010Location
Drawer
MiddleShelf
Middle, MiddleWall
West wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Scott LonganDate
September 26, 2009Location
Container
RightDrawer
BottomShelf
LeftCabinet
Case# 30Wall
EastBuilding
Freida Smith HallCategory
Permanent