Cracked Stone Brick

Cracked Stone Brick is a new block type that was implemented in the 1.8 Beta update. It can be found in Strongholds, which were also implemented in the 1.8 update. It can also be crafted (in an unconventional manner) by creating stone brick stairs, and mining them while they are not touching stone, and are not near water (these produce different results).

Trivia

 * It appears that, as of 1.8 pre-release, these blocks act like mushroom cap blocks, generating a differing texture once via location.