Hyalite is an amorphous type of Opal that is associated with volcanic activity. It is very clear and glassy and typically takes a globular form. Unlike it's more famous cousins, this form of opal rarely shows any color play. Hyalite is also known as "Water Opal", Jalite, or "Muller's Glass" - the latter after the man who discovered it.
Hyalite contains trace amounts of uranium, which makes it very mildly radioactive. It fluoresces a bright green under UV light, like "Vaseline Glass" does. The amount of fluorescence varies according to how much uranium is present - some glow strongly, some weakly.
The specimens being offered here fall into three size groups : small, medium, large. The smallest are micromounts, the medium are thumbnails, and the large are select larger thumbnails. The smallest weigh about 2 grams and measure approx. 2-3cm across, the mediums weigh about 4-5 grams and measure approx. 3-4cm, and the largest weigh about 10 grams and measure approx. 5-6cm. These sizes and weights are approximate and your specimen may vary slightly.
Refer to the photos. The black centimeter cube is shown for scale and is not included. You are purchasing ONE (1) specimen selected from the larger lot shown. Your purchase will include an ID label.
