ROCK   CRYSTAL
Colorless quartz; very abundant in facet-grade crystals to several pounds weight; large flawless pieces capable of cutting spheres in excess of 3″ are rare and cost rises sharply as size increases above this; electronic-grade crystals of 5-10 lbs. may realize as much as f50.00 per pound; much of facet material is left over from the extensive mining for electronic quartz in Brazil during World War II; Brazil continues to be the largest supplier, but good material is available from Arkansas as well as from many other places in the world.
ROSE   QUARTZ
Translucent to nearly transparent; from very pale pink to medium rose, some¬times with a bluish tinge; also chatoyant but rarely so pronounced that good star or catseye cabochons can be cut; favored for carvings. Value depends upon intensity of hue coupled with approach to transparency; mainly supplied by Brazil but also from Madagascar, South Dakota, and Canada.
RUTILATED  QUARTZ
Recently in abundance from Brazil in fair to superb material containing brilliant coppery to golden rutile fibers in colorless to medium smoky quartz; some fibers occur in broad blades to i/2″ wide, others appear in stellate patterns upon small black tabular hematite crystals; crystals to 10 lbs. weight. Used mainly for specimen pieces but also for cabochons, carvings, and ornamental items.