Question about plantar warts

I don't have these now, but I think I did have one when I
was a kid in the early 80s. At the time I didn't know what
they were. I remember getting a flat, disc shaped grey mark
on the instep of my sole. At the time I was in swimming
lessons. After my mom noticed, we went the doctor for an
examination, and he prescribed some thick, evil smelling
liquid from a small bottle with a glass probe on the lid,
which my mom would use to paint the top of the lesion. Then
she would cover it with cream and put a tape bandage on it.
The liquid and cream wouldn't hurt, but then I remember when
the 'cap' came off. She peeled off the bandage one day, and
instead of the normal surface, there was a cavity with a
bunch of tiny stalks inside, almost like the surface of your
tongue, only white. I remember it so vividly because when my
mom put the liquid on, it was like somone was jabbing white
hot needles in my foot. I was researching another illness,
when I rembered my childhood experience and went looking for
the information. I figured out that it was probably a
plantar wart, but does anyone know where I can find a
picture of the top of one that's open? All I've seen online
are closed, and look more like callouses and corns than what
I remember.