Dear all, I have obtained this piece with others from a former collector, with indication of "Imilchil, Morocco". It is 10 cm across. Since I have never seen this kind of stilbite from that place, is there anyone that could add info about that?
Sorry to see no experts chimed in on this topic. This mineral is quite common and fine specimens have been found in many continents and many different countries. I've found stilbite in Golden, Colorado, but the crystals rarely exceed a centimeter but some crystals can have similar shape as yours. I've got a specimen from New Jersey that has a similar color, but the morphology is little different, not quite as "flowering" or bulbous as your specimen.
I checked Mindat's gallery for Imilchil, and there are some specimens that have similar shape as yours, but those are a vibrant orange in color. The specimens that are more milky in color like yours seem to look different, they are more the sheaf-shaped type. However, that is not to say that yours did not come from that location. Its just too hard to tell.. Being that this is stilbite, I don't think you'll ever get a definitive answer honestly... I'd just say its from there as that is what the dealer claimed if you trust them.