Without seeing a picture I would guess that it's a tournament chip.

Agree. I am a member of the Casino Chip & Gaming Token Collector’s Club. Could help if you gave more info and picture would be best. Does it say “no cash value” on it? What color is the chip? What casino is it from? I do know there are some bright orange Dunes $25,000 chips floating around out there that are over-sized chips. These are real. Another option is to try looking up “the Chip Guide”. This is a great website and shows all sorts of casino chips.

It's the chip I used for my profile picture.

@sramsey5star does the chip actually say “poker atlas” on it? If so, it is not a real casino chip. A very high percentage of real casino chips also have a location on them. Something like “Las Vegas, NV.”

The Poker Atlas chips were a give away from this site at some poker atlas meetup tournaments done early in the website's history.