When you cause gravel or sand to fall, the FallingSand entity has a blue or green texture until it turns into the block again. The color depends on the side from which you observe the entity.
When you cause gravel or sand to fall, the FallingSand entity has a blue or green texture until it turns into the block again. The color depends on the side from which you observe the entity.
Confirmed for 14w27b. Same happens for anvils, red sand and even dragon eggs.
Sometimes the fallingsand texture is blue, sometimes it's green, sometimes it's black and sometimes the falling sand just disappears, and reappears when back on the ground.