Name/Title
LabradoriteEntry/Object ID
2013.1.17Description
Chemical Composition: SiO2
Crystal System: Triclinic System
Description: Common Name: Labradorite
Chemistry: (Ca,Na)(Al,Si)4O8, where Ca/(Ca + Na)
Group: TectoSilicates
Location: Labrador, Canada
Description:This a small slab polished on one side. The colors vary from brilliant blues to green in a iridescence.
Physical Description:
Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2.
There are many different varieties of quartz, several of which are semi-precious gemstones. Especially in Europe and the Middle East, varieties of quartz have been since antiquity the most commonly used minerals in the making of jewelry and hardstone carvings
Fracture: Uneven to Conchoidal
Hardness: 6 Orthoclase
Luster: Pearly
Rock Type: Sedimentary
Specific Gravity: 2.68-2.72
Streak: White
Variety: Labradorite ((Ca, Na)(Al, Si)4O8), a feldspar mineral, is an intermediate to calcic member of the plagioclase series. It is usually defined as having "%An" (anorthite) between 50 and 70. The specific gravity ranges from 2.68 to 2.72. The streak is white, like most silicates. The refractive index ranges from 1.559 to 1.573. Twinning is common. As with all plagioclase members the crystal system is triclinic and three directions of cleavage are present two of which form nearly right angle prisms. It occurs as clear, white to gray, blocky to lath shaped grains in common mafic igneous rocks such as basalt and gabbro, as well as in anorthosites.Collection
RAGM Mineral CollectionAcquisition
Accession
2013.1Source or Donor
Crater Rock Museum (Misc. donors)Acquisition Method
GiftDimensions
Width
2-1/2 inDepth
1/4 inLength
3-1/2 inLocation
Location
Shelf
CS-D-2Room
Curation StorageBuilding
Crater Rock MuseumCategory
StorageMoved By
Curtis GardnerDate
January 3, 2024
