Sterling Agate Necklace 16”

Originally from Mineral World Smithsonian from what I’ve been told is a lace agate. I am going by that I really don’t know anything about stones.16” sterling chain pendant measures approximately 1 3/4” with bale. Please use photos as true description. Shows very little wear. Comes with small Mineral Shop Bag.Cannot guarantee item is from pet or smoke free environment.Item may be from yard sale,thrift shop or estate sale.I have no control over exposure to smells.Please consider before purchasing