Free-form shape Montana Agate Cabochon gemstone pendant necklace finished with high polish. Sterling silver bail and genuine black leather 2mm cord, 17 inch in length and completed by a sterling silver hook and eye clasp. Pendant: 1 3/4 inch. Width, 3/4 inch.
Montana Agate is typically clear to slightly yellow with red, brown, or black spots or dendrites. The red color is the result of iron oxide, the black is the result of manganese oxide. It is considered a moss agate or dendrite agate.
Montana Agate is believed to be 50 million years old. Orginally formed in the Yellowstone National Park area of Wyoming and found near the Yellowstone River in Montana. The vein runs from the Yellowstone National Park in Wyoming to North Dakota. Montana Agate is one of the alluvial agates found in gravel deposits scattered over a huge area encompassing thousands of square miles. The best agate hunting is done by boat in the late fall when the water level is low.
Montana Agate has been the state of Montana's official state gemstone (along with Montana Sapphire) since 1969.