Name/Title
Botryoidal AgateEntry/Object ID
2013.1.8Description
Chemical Composition: SiO2
Crystal System: Monoclinic System
Description: Common Name:Carnelian
Chemistry: SiO2
Group: Silicates
Location: Chihuahua, Mexico
Description: This is a semi-spherical rock with a void in the center. It is polished throughout. The colors vary from browns to tans with dull reds.
Physical Description:
Carnelian (also spelled cornelian) is a brownish-red mineral which is commonly used as a semi-precious gemstone. Similar to carnelian is sard, which is generally harder and darker (the difference is not rigidly defined, and the two names are often used interchangeably). Both carnelian and sard are varieties of the silica mineral chalcedony colored by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration. It is most commonly found in Brazil, India, Siberia, and Germany.
Fracture: Conchoidal
Hardness: 7 Quartz
Luster: Waxy
Rock Type: Sedimentary
Specific Gravity: 2.65
Streak: Light BlueCollection
RAGM Mineral CollectionAcquisition
Accession
2013.1Source or Donor
Crater Rock Museum (Misc. donors)Acquisition Method
GiftDimensions
Width
3-1/2 inDepth
4-7/8 inLength
5-3/8 inLocation
Location
Display Case
FS-3Room
Frieda Smith HallBuilding
Crater Rock MuseumCategory
PermanentDate
August 18, 2023
