Used Block
From the Super Mario Wiki
An Used Block from New Super Mario Bros. Wii.
Used Blocks appear when Mario or Luigi hit a ? block or a Brick Block with an item inside. Used Blocks are usually square and brown with rounded edges. In Super Mario World, Used Blocks had small, closed, angry eyes. Also, in Super Mario World if the player hits a P-Switch, all Used Blocks will turn into coins and vice versa for a short time.


