Natural Yellow Hematoid — Gross

Yellow Hematoid is a variety of quartz (SiO₂) that contains inclusions or impregnations of iron oxides and hydroxides, specifically goethite (FeO·OH) and limonite, dispersed in the silica matrix during crystalline growth. It forms in hydrothermal veins and zones of supergenic alteration, where iron-rich solutions percolate and interact with the forming quartz. The yellow to orange-yellow color results from the presence of goethite and limonite, hydrated iron oxides that absorb specific wavelengths of visible light. The irregular distribution of these inclusions in the quartz matrix creates patterns, clouds and color gradations characteristic of each specimen. Hardness: 7 on the Mohs scale. Density: 2.65 to 2.90 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