Agate is a type of chalcedony, a milky form of quartz, that
appears in a striking banded formation which people have found aesthetically
pleasing for centuries. Chemically, it is identical to quartz, amethyst, and
carnelians, but because it forms in a different way, agate looks radically
different. Like all forms of chalcedony, the chemical formula for an agate is
SiO2, and the colors come from impurities in the silicon dioxide, however, Agate
is a very complex rock. Pockets in
rocks fill with water and gas, crystallize and over time you have an agate,
simply put. Agate is a very complex rock.
Crazy Lace Agate from Mexico
The Montana Moss Agate is known for the dendrite, pictures of
trees or moss, and ribbon effect; sometimes called Sergeant stripes in a rock. The
name given to the beautiful chalcedony found most abundantly in the alluvial
gravels of the Yellowstone River probably should be named the Yellowstone Agate;
the genesis was centered in the Yellowstone
Park
.jpg)
Montana Moss Agate is a semi-precious stone and in
1969, Montana Legislature passed legislation making the agate the state's
official gemstone along with the Montana
sapphire. Montana
Moss Agate can be
found in many colors from dark (almost black) to brown to orange or green
to clear. Montana
Agate values have soared with its increasing scarcity.
