Rose quartz: why the pink is so soft
Rose quartz almost never grows as crystals. It forms in solid masses, coloured by fibres far too small to see.
Most coloured quartz gets its colour from atoms inside the crystal. Rose quartz is different. Studies have shown that its pink comes from microscopic fibres of another mineral, related to dumortierite, spread through the quartz. The fibres also scatter light, which is why rose quartz looks slightly hazy and soft rather than glassy.
Rose quartz usually forms as solid masses in pegmatites, coarse granite-like rocks, with no crystal faces at all. Well-formed pink crystals do exist, but they are rare collector pieces. The massive habit is good news for carvers. Rose quartz comes in big, solid blocks that can be cut into spheres, hearts, towers and bowls.
Brazil and Madagascar supply much of the world's rose quartz, with more from Mozambique, South Africa and India. The colour runs from almost white to a deep pink, and a deeper, more even pink earns the higher grade.
Strong sunlight can fade it over time, so the classic advice holds. Show rose quartz in good light, but keep it out of the afternoon sun in a window.
The pink in rose quartz comes from mineral fibres far too small to see, not from the quartz itself.
