If your rock is a single mineral, it may be an obvious crystal or look more worn and rounded. For example, when a quartz ...
Recently, author JG discovered a deposit of rock crystal quartz in El Dorado County in east-central ... Nathan Renfro is analytical manager of the gem identification department and microscopist of the ...
Its finest quality is highly transparent and usually faceted. GIA evaluates rose quartz but does not grade it. A GIA Colored Stone Identification Report assesses the characteristics of any polished, ...