These opals, hyalite variety, are a novelty we brought from Tucson 2014. They are very transparent and forming mammillary aggregates with an excellent brilliance. We would like to emphasize their fluorescence, from green to yellowish, clearly visible under sunlight (which contains ultraviolet radiation). It is known the fluorescence of hyalite opals under ultraviolet light, but it is not so common that it happens with this intensity under the sunlight. They also exhibit activity under fluorescent lamps and under the LW-UV light (very intense) and SW-UV. They aren’t active under warm halogen bulbs. A very aesthetic and scientific interesting specimens.