Glowstone
From World of Entorais Wiki
About
Glowstones are perfect cubes of translucent white crystalline material that is extremely resilient. They do not occur naturally, instead being recovered from ancient ruins. They have been discovered in various sizes, but evenly scaled: 2cm, 4 cm, 8cm, 16 cm.
Powers
In darkness or low light conditions they emit a faint blue glow that slowly pulses. Some claim that leaving said cube in the full light of the sun increases the rate of the pulsing. Aside from this behaviour, their purpose is unknown.
Location
Glowstones are most often uncovered in ancient ruins. Some are kept as curiosities to study by various scholars, or private treasures by collectors.