Name/Title
Tourmaline var. VelvetEntry/Object ID
2014.1.125Description
Crystal System: Hexagonal System
Description: Common Name: Tourmaline var.Velvet
Chemistry: (Ca,K,Na,[])(Al,Fe,Li,Mg,Mn)3(Al,Cr, Fe,V)6
(BO3)3(Si,Al,B)6O18(OH,F)4
Group: Silicates
Location: Sonora,Mexico
Description: A columnar shaped piece with a twinned fragment of another.Color is black and velvety. Complex cluster of black Schorl Tourmaline crystals in stalactitic form. The surface of the specimen are covered with fine crystal faces giving it a velvety surface texture. This material is sometimes known as "Velvet Tourmaline". Ex. Joseph D'Agostino collection 4FA.
Locality Milopilas, Sonora, Mexico
Physical Charateristics:
Tourmaline is a crystal boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Tourmaline is classified as a semi-precious stone and the gemstone comes in a wide variety of colors. The name comes from the Sinhalese word "Thuramali" (??????) or "Thoramalli" (????????), which applied to different gemstones found in Sri Lanka.
Fracture: Conchoidal
Hardness: 8 Topaz
Luster: Vitreous
Rock Type: Igneous
Specific Gravity: 2.68-2.72
Streak: WhiteCollection
RAGM Mineral CollectionAcquisition
Accession
2014.1Source or Donor
Crater Rock Museum (unknown donors)Acquisition Method
GiftDimensions
Width
1-1/4 inDepth
1-1/4 inLength
3 inLocation
Location
Shelf
CS-I-3Room
Curation StorageBuilding
Crater Rock MuseumDate
January 31, 2024Location
Cabinet
G-1 frontWall
NorthBuilding
Storage (old gift shop upstairs)Category
Permanent