you go to the haunted mansion in Eterna forest then go on the left side of the mansion then press A (the button) on the brown side of the hill then you get it and it said something about bringing it to the owner then you go in the mansion and go to the first floor dining room and you will see a man floating by then i do not know because i cant find the right question so i hope it helped!
You can search on youtube. that's where i found mine.search Pokemon PLatinum plate locations.
there is no such thing as a "Curse Plate."
Underground!
Arceus (With Dragon plate)
you can get iron plate by using explorer kit
a fist plate
Finding the Insect Plate in Pokemon Diamond requires the use of the HM Cut. It is in Eterna Forest hidden in the wall to the right of the Old Chateau.
purple
Yes, in the old chateau, but it is called the "insect plate".
you have to dig it up when you are underground
if a Pokemon holds a plate (arceus) and a Pokemon uses flail the shards restore the plate because flail breaks the plate.
no there is no such thing as the polychromatic plate