Smoky Quartz Q.A. - Gross

Quality A Smoky Quartz is a variety of quartz (SiO₂) selected for its high transparency and uniform color, with a minimum incidence of inclusions, fractures or internal turbidity. Its color — which varies from light brown to dark gray, and can reach almost black tones — results from natural exposure to gamma radiation from radioactive elements present in the surrounding rocks, such as uranium and thorium, which generate defects in the quartz crystal lattice associated with color centers involving aluminum and hydrogen ions. It forms in granitic pegmatites and hydrothermal veins, in the same environments as hyaline quartz. The Quality A classification indicates specimens with homogeneous color distribution, high definition of the crystalline faces and absence of visible structural defects, placing them at the top of the commercial selection scale for the species. Hardness: 7 on the Mohs scale. Density: 2.65 g/cm³. Crystalline system: trigonal. Available variations, approximate data: 1 to 3 cm — Approx. 0.010 kg — 250 pcs per kg 3 to 6 cm — 0.030 to 0.150 kg — 30 pieces per kg 6 to 15 cm — 0.150 to 0.800 kg — 2 to 3 pieces per kg