Where do you find a dawn stone in Nimbasa City?

You can't find a Dawn Stone in Nimbasa City. Dawn Stones are not found in the wild in Pokemon games. You can obtain them through other means, such as:

* Trading: You can trade with other players or with NPCs who are willing to trade them.

* Finding them in certain locations: Dawn Stones may be found in specific locations in some games, but not in Nimbasa City.

Keep in mind that the availability of items and their locations can vary depending on the specific Pokemon game you are playing.