This is beautiful semi precious gemstone Graveyard Point Plume Agate from near Graveyard Point in the Owyhee Mountains of far eastern Oregon, near the Idaho border.
The agate formed in the cracks in basalt. The veins of agate range from 1 inch to about 18 inches thick, and can be a few feet long to 30 feet in length!
These agate cabochons have white to yellow plumes. The black or metallic looking wisp are Marcasite. Sometimes even opal has occurred in the material.
Plume Agate gets its name from its beautiful plume like inclusions. These unique gemstone designer cabochons are partly translucent.
Agate is a member of the chalcedony family, or a microcrystalline quartz, and it has a hardness of about 7 on the Moh's scale. The name is derived from its occurrence at the Achates River in southwestern Sicily.
Agate was highly valued as a talisman or amulet in ancient times. It was said to quench thirst and protect against fever. Persian magicians used agate to divert storms. Mithridates, king of Pontus, had a collection of thousands of agate bowls. Agate bowls were also popular in the Byzantine Empire. Collecting agate bowls became common among European royalty during the Renaissance and many museums in Europe, including the Louvre, have spectacular examples.
Metaphysical Properties of Plume Agate: In general Agate cabochons are said to be stabilizing and strengthening. They improve memory and increase energy.