Is it concievably possibe for a Morrel mushroom, to become fossolized or petrified and still basically retain its original shape, my wife has a rock, which looks like the top of a mushroom, with approximatly 1/2 inch of the stem, where it was broken off, it is approximatly 1 and a 1/2 inches tall, approximatly 1 and a 1/2 inches wide, and 1 inch thick, it is porous around the stem piece where it attaches to the head of the mushroom, and a light to darker color, with what looks like a fine silica crystals or calcium deposits in the holes around where the stem attaches to the head its rough and nodually on the head and the stem is realitivily smooth, I would post a picture, but unable to do so, so tried to describe it as good as possible, but mainly wanted to know if this was possible, all replies would be appreciated, thank you.