Thousand Layer, often sold as Thousand Layer Jasper, is a trade name for an opaque, silica-rich stone characterized by numerous thin, wavy, concentric, or landscape-like layers. It is generally composed primarily of microcrystalline quartz or chalcedony, with its varied colors and patterns created by iron and manganese oxides, clay minerals, volcanic material, and other impurities. The stone forms gradually through repeated sediment deposition, silicification, and mineral alteration in sedimentary or volcanic environments. It is most commonly associated with Madagascar, although similar material may also be found in India, Indonesia, Mexico, and other regions known for jasper.

In metaphysical traditions, Thousand Layer is believed to promote grounding, stability, patience, and emotional balance. Its many layers are often viewed symbolically as representing accumulated experience, personal history, gradual growth, and the ability to see situations from different perspectives. It is also sometimes associated with perseverance, transformation, and a deeper connection to the Earth. These metaphysical properties are spiritual beliefs and have not been scientifically proven.