QUARTZ
Species: Quartz
Mohs Hardness: 7 out of 10 Color: Occurs in many different colors. Scroll below for a list of the different varieties of quartz. RI: 1.544 to 1.553 (very constant) Birefringence: 0.009 SR/DR/AGG: DR Clarity Type: Type II Optic Character: Uniaxial positive. Might show a bull's eye or Airy's spiral optic figure under crossed polarizing filters. Pleochroism: Weak to moderate, colors vary depending on variety of quartz. Spectrum: Not diagnostic Fluorescence: Generally inert SG: 2.66 (+0.03/-0.02) Routine Treatments: Varies Additional Enhancements: Heating, irradiation, dyeing, impregnation |