I have had this here A rock or fossil whatever it is for a few years I can't remember where I got it from but but it was here in Arizona I would say it's about an inch and a half wide in about 2 inches tall
Sry, I forgot about this. The outlined red area is interesting, but I don’t have enough to go on by just this picture. It’s possible you only have one side and the white section appears to be the interior and was a calcium mineral before permineralization. It looks like it’s calcite now, so that makes sense. The outlined red area is a different mineral, probably quartz. The reason for the two different petrifications is the mineral makeup prior to fossilization.