When placed in the world, the source block will also gradually float upwards to the highest solid block whenever possible. Above a certain y-level (default at y=120), it will always condense into a block of Glowstone. In addition, when placed above 80% of the "threshold level" (i.e. y=96 by default), the source block will condense randomly. The properties can be switched off in the configuration file.
Upon contact, the player will be applied with the Jump Boost and Speed effects for 6 seconds and the Glowing effect for 30 seconds.