Here is the full list of all 23 Coin Treasures achievements.
Collect 10000000 Coins
Have 1000000 Coins in your Bank Account
Collect a Red High Value Mega Coin
Collect 1000000 Coins
Collect a Mythic Artifact
Collect a total of 100 Red High Value Coins
Collect a total of 100 Silver Coins
Collect a total of 100 Green High Value Coins
Collect a Legendary Artifact
Regenerate 1000 Coins
Defuse a "The Bomb!" Powerdown
Win a Black Flag Jackpot
Collect 100000 Coins
Collect an Epic Artifact
Activate a Lightning Powerdown
Collect 10000 Coins
Collect a Rare Artifact
Collect 1000 Coins
Collect 100 Coins
Collect a Magic Artifact
Activate a Sticky Pins Powerdown
Collect a Normal Artifact
Unlock Steam Achievements in the Treasure Shop