Common Mistakes

[Nyororin]

Originally Posted by MMM

Though in colloquial Japanese you will hear young Japanese play with these い and な adjectives. きれい is a な adjective, but I hear people say きれかった meaning "It was pretty" instead of きれいだった.

But your opposite example is never cool.

I have NEVER heard anyone say "きれかった", not even once. Maybe it`s a specific dialect?

[blimp]

yes, u will hear that a lot more in kansai. or perhaps exclusively in kansai.someone else with have to confirm the last thing.
i'm not sure it has really anything to do with dialect. and i can't on top of my head think of any other adjective that would work be used the same way.