Terahertz, an artificial mineral made of silicon, is not a natural stone. Terahertz ore is said to be a stone that emits a frequency that vibrates about one trillion times per second. Terahertz waves are a type of electromagnetic wave that emits a long frequency, with a wavelength of 3μm to 1000μm between 1 trillion Hz and 100 Hz, possessing the properties of both light and radio waves. Its vibrations are said to promote blood circulation, relieve stiffness, and are attracting attention as a stone that is effective for beauty and health. According to NASA, these terahertz waves are "transmission wavelengths" that penetrate matter and reach human cells, thus having an activating effect, and research is currently underway worldwide. It is a popular mineral that is sold at a considerable price. I wear it every day myself, and I have obtained some, so I will put it up for sale.