Okay kiddo, have you ever played with Play-Doh? When you squish and mold it into different shapes, it’s still the same stuff but it looks different, right? Well, in rocks, something similar can happen.
Imagine a mineral, which is like a tiny rock, that forms inside another mineral. But then something changes, and that first mineral turns into something else. The thing is, sometimes the second mineral can keep the same shape as the first mineral, even though it has a different chemical makeup! That’s a pseudomorph - it’s like a mineral imposter, pretending to be something it’s not.
So, if you found a rock with a pseudomorph inside, you might see a crystal that looks like it’s made of one thing, but when you look closer, you’ll see it’s actually made of something else entirely! Pretty cool, huh?