Item Description
The "skeletal" nature of the crystal is seen in the uniquely embossed lines which run about its surface. These lines indicate little "foundations" of where more crystals were on the verge of growing, yet were washed away in the rivers and streams they are found in.
Quartz
The Universal Crystal
Properties of Quartz
Physical Properties
Category:
Silicate Mineral
Chemical Formula:
SiO2
Crystal Class:
α-Quartz: Trapezohedral; β-Quartz: Trapezohedral (Class 6 2 2)
Crystal System:
α-Quartz: Trigonal; β-Quartz: Hexagonal
Dana Classification:
75.01.03.01 (Tectosilicates)
Name:
Quartz
Space Group:
α-Quartz: P3221 (no. 154), β-Quartz: P6222 (no. 180)
Strunz Classification:
4.DA.05 (Oxides)
Synonym:
Agate, Amethyst, Aventurine, Carnelian, Cat's Eye, Chalcedony, Chert, Chrysoprase, Citrine, Flint, Hornstone, Jasper, Moss Agate, Plasma, Prase, Rock Crystal, Rose Quartz, Sapphire Quartz, Smoky Quartz, Tigers Eye
Unit Cell:
a = 4.9133 Å, c = 5.4053 Å; Z=3
Mineral Identification
Birefringence: +0.009 (B-G interval)
Cleavage: {0110} Indistinct
Common Colors: Colorless, Various depending on inclusions
Crystal Habit: 6-Sided Prism, Hexagonal Terminations, Drusy, Massive, Microcrystalline
Diaphaneity: Transparent to Opaque
Formula Mass: 60.083 g·mol−1
Fracture: Conchoidal
Luster: Vitreous to dull
Melting Point: 1670 °C
Mohs Hardness: 7
Optical Properties: Uniaxial (+)
Pleochroism: None
Refractive Index: nω = 1.543–1.545, nε = 1.552–1.554
Specific Gravity: 2.65
Streak: White
Tenacity: Brittle
