පළිඟු Quartz crystal cluster from Tibet General Category Silicate mineral රසායනික සූත්‍රය SiO2 Strunz classification 04.DA.05 Dana classification 75.01.03.01 Crystal symmetry Trigonal 32 Unit cell a = 4.9133 Å, c = 5.4053 Å; Z=3 Identification පාට / පැහැය Colorless through various colors to black Crystal habit 6-sided prism ending in 6-sided pyramid (typical), drusy, fine-grained to microcrystalline, massive Crystal system α-quartz: trigonal trapezohedral class 3 2; β-quartz: hexagonal 622[1] Twinning Common Dauphine law, Brazil law and Japan law Cleavage {0110} Indistinct Fracture Conchoidal Tenacity කැඩෙනසුළු Mohs scale hardness 7 – lower in impure varieties (defining mineral) Luster Vitreous – waxy to dull when massive Streak සුදු Diaphaneity Transparent to nearly opaque Specific gravity 2.65; variable 2.59–2.63 in impure varieties Optical properties Uniaxial (+) Refractive index nω = 1.543–1.545 nε = 1.552–1.554 Birefringence +0.009 (B-G interval) Pleochroism නැත Melting point 1670 °C (β tridymite) 1713 °C (β cristobalite)[1] Solubility Insoluble at STP; 1 ppmmass at 400 °C and 500 lb/in2 to 2600 ppmmass at 500 °C and 1500 lb/in2[1] Other characteristics Piezoelectric, may be triboluminescent, chiral (hence optically active if not racemic) References [2][3][4][5] වර්ග (පාට අනුව)[සංස්කරණය] පාට / පැහැය නම කිරි පැහැය තිරුවාණ දම් දඹ පළිඟු කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ කොටුවේ පෙළ ↑ 1.0 1.1 1.2 Deer, W. A., R. A. Howie and J. Zussman, An Introduction to the Rock Forming Minerals, Logman, 1966, pp. 340–355 ISBN 0-582-44210-9 ↑ Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W. and Nichols, Monte C., ed. "Quartz" (PDF).