Red Coin
Red Coins were first seen in Super Mario World 2: Yoshi's Island. In which, they were hidden behind regular Gold Coins. The only way to tell which Coins hid Red Coins was to grab it, or use a Magnifying Lens. There were twenty coins in each level, and counted as twenty points for your score at the end of the level.
They were later see again in Super Mario 64 and Super Mario 64 DS, in which one was worth two Gold Coins. Collecting all eight in one course would make a Power Star appear over a Star Marker.
They made another appearance in Super Mario Sunshine. This time, collecting all eight would make a Shine Sprite appear.
In New Super Mario Bros., a Red Ring appeared in some levels, making eight red coins appear. If Mario or Luigi collected them all in the time limit, they were awarded with a power-up.
Red Coins are the most used secondary coins.
