Before 2000, small tugtupite pieces (2" to 3") were selling for $500 or more. They earned the moniker "King of Fluorescent Minerals" due to the rich red color and brightness. In 2001 I started supplying pieces to the market, prices dropped, and we haven't looked back. Quality pieces still garner top dollar, but the sizes have also increased (such as this piece). Shortwave shown below followed by an animation showing the color change after exposure to UV (tenebrescence), then a gallery of pics under midwave, longwave, and white light.