There's nothing precious about this Roadblock.

On Friday's episode of The Amazing Race (8/7c, CBS), racers have go mud-diving in El Tutomo, a Colombian mud volcano, to retrieve an emerald. Needless to say, the end result is not pretty.

"You look like Gollum," Tyler tells a mud-covered Korey as he climbs out in the exclusive sneak peek above. "Looking for the ring!"

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That's not entirely inaccurate, since Korey drops the emerald on his way down. Check out the full clip above to see if he finds it again.

The Amazing Race airs Fridays at 8/7c on CBS.

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