Prasiolite is a pale-green form of quartz and is becoming popular as an inexpensive green gem for jewelry. ... Sphene is more ...

Other factors, such as clarity, carat size, and cut will also determine the value of your alexandrite. Low-quality ...

The Smithsonian’s National Museum of Natural History will put the “Lion of Merelani,” which is one of the most finely detailed colored gemstones in the world, on public view starting Thursday.