These are some of my favorite stones. They're translucent, which means that light comes through them, but in a very soft diffuse sort of way. The stones look like a misty morning in a fall landscape where occasional fall colors of orange, brown, and red peek through.
The stones come from Montana, from agates found along the banks of the Yellowstone River. The river got its name from Native Americans who called it the Yellow Stone River in their language. That name was translated into French by the French-Canadian trappers, and later Lewis and Clark translated the name into English.
Agates are a form of chalcedony made up from silicon dioxide, or basically quartz. They have a Moss hardness of 7, just like clear quartz.
The colors inside Montana Moss Agates are due to small amounts of metals present as impurities. The red comes from iron oxides, and the black comes from manganese oxides.
Montana Moss Agates were formed by volcanic activity in the Yellowstone area during the Pleistocene age, roughly from 2.5 million years to about 12,000 years ago. The volcanoes produced the silicon dioxide, and then rainwater seeping into the rocks brought in the iron and manganese impurities, leading to wonderful bands and beautiful splashes of color in this translucent stone.
In a metaphysical sense, Montana Moss Agate is said to cleanse and balance all of the chakras.
You can see our selection of stones on our website, heartofstonestudio.com.