AI Explanation: Terahertz ore is an artificial ore made from high-purity silicon that emits approximately one trillion molecular vibrations (terahertz waves) per second. It is expected to have effects such as promoting blood flow, improving cold sensitivity, activating cells, and relieving stiffness, and is very popular as health and beauty goods such as necklaces, bracelets, and gua sha tools. It's a very popular stone in the market, but it's a strange stone that doesn't sell even when the price is lowered on Mercari.