Chalcedony. According to the information about the Chow Tai Fook Minnie Pendant, we learned that the stone of the Chow Tai Fook Minnie Pendant is made of chalcedony. It is a kind of mineral, actually a kind of quartz, the general name of the cryptocrystalline substance of SiO?, and it is not a precious gemstone. It's just Chow Tai Fook's brand and Disney's patent, so the price is relatively high.