Bonus Coin (Donkey Kong Country 3: Dixie Kong's Double Trouble!)

Bonus Coins are golden coins that appeared in the games Donkey Kong Country 3: Dixie Kong's Double Trouble! and Donkey Kong Land III. Bonus Coins can be earned by completing Bonus Levels (which are accessible via the hidden Bonus Barrels scattered across the Northern Kremisphere). Only one Bonus Coin can be earned per bonus level; the Kongs cannot earn another coin for completing the same Bonus Level twice. Bonus Coins can be given to Boomer, one of the Brothers Bear, allowing the demolitions expert to destroy the boulders that block access to the various levels of Krematoa. The same symbol on the Bonus Barrel is printed on the Bonus Coin.

Each level has two Bonus Coins, but there are a few levels in Krematoa that have three Bonus Barrels. Also, some bosses have a Bonus Coin in their possession.

Bonus Coins are similar to the Kremkoins from Donkey Kong Country 2: Diddy's Kong Quest and Donkey Kong Land 2. Both are earned for completing Bonus Levels and both are needed to access the Lost World of their respective regions.

Trivia
To get all 85 Bonus Coins without going through bonus levels, at the Select Game menu, highlight a saved game and press L, R, R, L, R, R, L, R, L, R then enter WATER. Go up to the waterfalls, play the the crystal game of Simon, and you'll receive 85 bonus coins.