These beautiful Moss Agate bowls were hand carved from natural stone. Agate is an ancient stone, known to have been used as early as 3500 years ago. Though I would guess that it was used long before any records show. It is a form of Chalcedony and shares its properties. Do not judge Agate's value by the fact that it is not an expensive stone and can be found fairly easily. It is NOT a common stone. The ancients knew that even then. I love using these natural stone bowls to hold my special stone circles.