Super value deal of 4 unique uranium Vaseline glass cullets which have Uranium Oxide Diuranate added. This causes each piece to be fluorescent and slightly radioactive. Each cullet (rock) you receive will glow a brilliant see thru green under UV light from UV Leds or UV flashlights (The G17126 LED is an excellent choice to light thses up.) Each of these rocks emit enough radiation to be detected by any of our sensitive Geiger counters. Every assortment will be unique and vary from the picture shown. Please be careful when handling as they have sharp points and edges! Sold in an assortment of 4.