High Quality Natural Solid fluorescent Mexican Opal Hyalite (Rare) Rough (mushroom) Mexico, Zacatecas 1 Piece 23.5 x 22 x 16 mm about 32.85 cts - 6.57 grams Untreated Green daylight-fluorescing hyalite opal was discovered in Mexico’s Zacatecas State in 2013. It occurs as botryoidal coatings commonly up to 1 cm thick along fractures and cavities in a poorly welded rhyolitic tuff. The material pos-sesses spectacular colour behaviour Fluorescence with long wave uv light the fluorescence can also be seen with normal light (but with less intensity) the piece for sale is what you see in photos! Standard shipping ( 2-7 days for Italy ) ( 10-20 days for Europe ) ( 15-40 days for rest of the world ) if you want fast shipping, please contact me immediately after the auction win