Atlantisite is a composition of purple stichtite in yellow/green serpentine, currently only found and mined in Australia. The stone contains the combined properties of Serpentine & Purple Stichtite, which makes it a perfect stone for assisting with guardianship, immune & blood strength, connecting with ancient wisdom, self esteem, and spiritual healing. I'm sure it has more amazing uses, too many to name here. A true powerhouse of a stone! Size is about 1.2" from top of bail to bottom of pendant. .0925 Sterling Silver setting, which is secure and substantial.