Barite and Quartz

White-reddish tabular Barite intertwined with colourless compact Quartz crystals. Lustre is vitreous. Sample is from a pegmatite. Quartz (SiO2) can have a variety of colours from white to purple. Lustre is vitreous or greasy and streak is white. Hardness is 7. Quartz usually occurs as long or short prismatic crystals that are terminated by double rhombohedrons and have striations crosswise. Quartz can also be granular, massive or disseminated. Barite (BaSO4) can be white, grey, colourless, or shades of blue, red, yellow or brown. Lustre is vitreous or pearly and streak is white. Hardness is 3 to 3 1/2. Barite tends to occur as thin or thick tabular crystals that can also be prismatic, compact, lamellar, fibrous or granular. Smallman Collection