In this particular group of gems, they are known as Carnelian; they have a hard reddish translucent semiprecious stone that is a variety of chalcedony.
They are the best available of its type and are usually less costly.
This type of Carnelian Gemstone can be found in many different variations of colors and can undergo many different changes.
With Iron being its origin of color, the Carnelian Gemstone can be heat treated without difficulty and as the iron is oxidized by the suns heat waves; this causes the tones of red in the gems to turn darker.
This Gemstone is called the Chrysoprase and are known by its bright green semiprecious stones as a variety of chalcedony.
The continuous distribution of colored light that is produced when a beam of white light is dispersed into its component, will show the stones to be none transparent and impervious to light, so that images cannot be seen through it.
I found that there have been people giving false accounts, of the Chrysolian Gemstones being sold as the highest grade of Jade, and that the greatest amount of Chrysoprase is a semiprecious stone that has a variety of chalcedony that comes from Australia.
The Prase Gemstone is a green form of quartz that comes from Eastern Europe and has a darker, yet less saturation, that is hardly ever found.
The meteorite, is a piece of rock that has reached Earth from outer space and has been found in small amounts of a green colored quartz that has been colored by chromium and they were found in Africa.
Copper Mineral, Chrysocolla Chalcedony is a green or blue-green copper silicate found around copper ores as a result of their reaction with water containing dissolved silica.
These gems are the most costly Chalcedony there are and they are solely found in Arizona.