Super Mario 64
Blue coins were first seen in Super Mario 64, and are worth 5 times that of regular coins. Blue coins are often seen after stomping on a Blue Coin Block. Mario uses a ground pound on these blocks to make a number of blue coins appear somewhere near him. After a certain amount of time, they disappear.
 Super Mario Sunshine
Blue coins were used far differently in Super Mario Sunshine then in Super Mario 64. Each stage in Super Mario Sunshine contained 30 blue coins. Corona Mountain has 10 blue coins, and Delfino Plaza and Delfino Airstrip have a combined 20, for a total of 240.
 Wario land 2
In Wario Land 2, blue coins could be collected, and were worth 100 regular coins.
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