Name/Title
KyaniteEntry/Object ID
2009.62.41Description
Chemical Composition: Al2 SiO5
Crystal System: Triclinic System
Description: Common Name: Kyanite
Chemistry: Al2 SiO5, Aluminum Silicate
Group: Silicates
Location: Minas Grais, Brazil
Description: The kyanite has blue thin fiberious crystals in a quartzite matrix.
PHYSICAL CHARACTERISTICS:
Color is blue usually but also can be white, gray or green. Color is often not consistent throughout the crystal and can be blochy or in streaks.
Luster is vitreous to almost pearly.
Transparency crystals are transparent to translucent.
Crystal System is Triclinic; bar 1
Crystal Habits include flat, pinacoid dominated, prismatic crystals often embedded in metamorphic rocks and quartz veins.
Cleavage is good in one direction parallel to the flat pinacoid face.
Fracture is splintery.
Hardness is approximately 4.5 when scratched parallel to the long axis of the crystal and approximately 6.5 when scratched perpendicular to or across the long axis.
Specific Gravity is approximately 3.58+ (above average)
Streak is white.
Associated Minerals are biotite, staurolite, garnets, quartz, andalusite and sillimanite.
Other Characteristics: Sometimes intergrown with staurolite.
Best Field Indicators are crystal habit, color, luster and unusual hardness
Fracture: splintery
Hardness: 5 Apatite
Luster: Vitreous
Occurrence: Kyanite in metamorphic rocks generally indicates pressures higher than 4 kilobars. Although potentially stable at lower pressure and low temperature, the activity of water is usually high enough under such conditions that it is replaced by hydrous aluminosilicates such as muscovite, pyrophyllite, or kaolinite.
Rock Type: Metamorphic
Specific Gravity: 6.5
Streak: white
Texture: crystaline
Variety: Kyanite is a polymorph with two other minerals; andalusite and sillimanite. A polymorph is a mineral that shares the same chemistry but a different crystal structure with another, or other, minerals. Kyanite is an attractive mineral that has a near sapphire like blue color in some especially nice specimens. Kyanite has a unique characteristic in that it has a wide variation in hardness, in the same crystal. The hardness of kyanite is approximately 4.5 when scratched parallel to the long axis of the crystal and approximately 6.5 when scratched perpendicular to or across the long axisCollection
RAGM Mineral CollectionAcquisition
Accession
2009.62Source or Donor
Museum Collection of MineralsAcquisition Method
DonationDimensions
Width
3-1/2 inDepth
2 inLength
6 inWeight
1.48 ozDimension Notes
Dimension taken at widest pointsLocation
Location
Container
RightDrawer
Top ShelfShelf
left, leftWall
South wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
PermanentMoved By
Wendy MondryDate
January 12, 2010Location
Container
RightDrawer
Top shelfShelf
LeftCabinet
Case #43Wall
South wallRoom
Delmar Smith HallBuilding
Crater Rock MuseumCategory
Permanent