Crystal healing is a pseudoscientific alternative medicine practice that uses semi-precious stones and crystals such as quartz, agate, amethyst, or opal. Crystal healing proponents believe that crystals and gemstones have properties that facilitate healing. the philosophy of modern crystal healing is based on traditional concepts borrowed from Asian cultures, most notably the Chinese concept of life-energy (chi or qi) and the Hindu or Buddhist concept of chakras, which are vortices of this life-energy, said to connect the physical and supernatural elements of the body. Practitioners of crystal healing believe they can boost low energy, prevent bad energy, release blocked energy, and transform a body's aura.