Colorful conch shell ishihara petrochemical treatment of rock specimen <----- I stumbled upon this under an ammonite for sale listing and i have never heard of this phrase or this "petrochemical treatment" ever before. Can anybody help me out with some imput (knowledge) as to what this process implies? and also if this means that most ammonite or other shelled fossils that has that rainbow or color crazy kind of look to it, does this mean they are real fossils but fake colored or yes there are real fossils that are naturally that rainbow or actually have undergone opalization?
Truely appeciate any and all help or advice
Thanks,
Sincerely Thomas.