Natural Quartzite Stone
Crystal system: hexagonal crystal system
Crystal: equiaxed, columnar, hexagonal biconical
Aggregate shape: massive, coarse-grained, stalactite
Hardness: Mohs hardness is 7
Cleavage/fracture: conchoidal fracture
Luster: glass luster
Color: none, white, with a little gray, yellow to orange, purple, deep purple, pink, gray-brown, brown, black
Streak: white
Proportion: 2.65 ~ 2.66
Other:
(1) Brittle
(2) With thermoelectricity
(3) Refractive index 1.533 ~ 1.541, birefringence difference 0.009, dispersion 0.013
(4) Quartz has a strong piezoelectric property (Piezoelectric property), that is, sparks will be generated when it is struck hard, which is the method of making fire with flint.
(5) Common inclusions in quartz are Hair crystal-mainly rutile; Grass crystal-mainly tourmaline; Water gall crystal-liquid inclusions in quartz; Celadon-light blue in it Rutile needles; milk quartz-turbidity caused by fine water holes; green quartz-composed of plate-like or fragmented chlorite, sometimes maybe green needle-like actinolite; aventurine-quartzite The inside contains green or reddish-brown mica flakes, also known as yao quartz, commonly known as aventurine. Common smoky black to dark brown smoky crystals is mainly due to the fact that these rocks contain a large amount of radioactive uranium and thorium.
