Carnelian is a form of chalcedony, a member of the quartz family.  Most Carnelian is heat treated  to enhance the reddish brown color.  Carnelian is a Zodiac birthstone for the signs of Leo and Virgo.  In folklore, carnelian was thought to help purify the blood and relieve menstrual cramps.  It's reddish brown color means it would mostly aid the red and orange (lower) energy centers (chakras). 

    Chalcedony is the name for a variety of stones in various colors and patterns made of small quartz crystals.  Some varieties are known by other names such as agate, jasper, bloodstone and tiger's eye.   Lapis Lazuli, which I covered previously, is a form of chalcedony.  The Romans used chalcedony as seals, and the Victorians carved them into cameos. Native Americans used chalcedony in sacred ceremonies.  It is thought to increase vitality and  emotional balance.  It's believed to banish fear and hysteria.  In folklore, it's used to treat eye problems, fever and gallstones.
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