Name/Title
Dendritic AgateEntry/Object ID
1988.6.136Description
Chemical Composition: SiO2 (MnO2)
Crystal System: Triclinic System
Description: Common Name: Quartz var.agate (dendritic)
Chemistry: SiO2
Class: Silicates
Location: COPCO, Southern Oregon
Description: Flat back with angular, polished face. Translucent creamy tan with one dark brown dendritic structure.
Physical Characteristics:
Dendritic agate is a whitish-gray or colorless chalcedony with tree- or fern-like markings known as dendrites. The variety name agate is used for this gem even though it does not exhibit the banding typical of agate.The dendrites in dendritic agate are iron or manganese inclusions, usually brown or black in color. Though they appear organic due to their fern-like structure, they are actually inorganic; they are formed at fine fracture surfaces through crystallization of weathered solutions of neighboring rock.
Fracture: Conchoidal
Hardness: 7 Quartz
Luster: Glassy
Occurrence: Quartz is an essential constituent of granite and other felsic igneous rocks. It is very common in sedimentary rocks such as sandstone and shale and is also present in variable amounts as an accessory mineral in most carbonate rocks. It is also a common constituent of schist, gneiss, quartzite and other metamorphic rocks. Because of its resistance to weathering it is very common in stream sediments and in residual soils.
Rock Type: Sedimentary
Specific Gravity: 2.65
Streak: White
Variety: Quartz is the most common mineral on the face of the Earth. It is found in nearly every geological environment and is at least a component of almost every rock type. It frequently is the primary mineral, >98%. It is also the most varied in terms of varieties, colors and forms. This variety comes about because of the abundance and widespread distribution of quartz. A collector could easily have hundreds of quartz specimens and not have two that are the same due to the many broad catagories.Collection
Boyd KlineAcquisition
Accession
1988.6Source or Donor
Boyd KlineAcquisition Method
GiftDimensions
Width
1-1/2 inDepth
3/8 inLength
2 inLocation
Location
Container
LeftDrawer
Front Row / BottomShelf
Left, LeftWall
NorthRoom
Freida Smith HallBuilding
Freida Smith Hall:Category
PermanentMoved By
Steve MillerDate
August 16, 2011Location
Container
LeftDrawer
Front Row / 2nd ShelShelf
Right, RightWall
EastBuilding
Founders RoomCategory
PermanentMoved By
Steve MillerDate
August 16, 2011Location
Cabinet
Case# 10Building
Menzter HallCategory
Permanent
