Uranium Glass Marbles

Because of the uranium content, these marbles glow bright green under ultraviolet light. The most typical color of uranium glass is pale yellowish-green, which in the 1930s led to the nickname Vaseline glass based on a perceived resemblance to the appearance (which was a yellow-green color) of Vaseline brand petroleum jelly as formulated and commercially sold at that time. Specialized collectors still define Vaseline glass as transparent or semi-transparent uranium glass in this specific color. https://stemcelltulsa.com/products/yellow-uranium-glass-ball