Different trace elements can produce other colors, allowing beryl to form semiprecious stones such as aquamarine. Minerals and gems are classified by their physical properties, including hardness ...

These stones represent the geological diversity of colored stone formation from the earth’s near surface in the crust (amethyst) to the mantle (peridot). Photo by Maha Tannous; courtesy of Apache Gems ...

stones, gems, and rocks?” Are they just different names for the same shiny thing, or are there subtle distinctions between them that matter for your metaphysical practice? I’m going to use the ...

Figure 1. Tiny but precisely cut and highly saturated stones were offered at Tucson. Photo by Eric Welch. At the AGTA and GJX shows, China Stone (Bangkok) marketed a selection of tiny, precisely cut ...