Land of the Lustrous

In the far-off future depicted in Land of the Lustrous, the Earth has been ravaged by meteors that have impacted it six times. Nearly all life was eliminated, and the surviving country was reduced to a single seashore. Over eons of time, a new species of sentient life—immortal diamonds that assume the shape of humans—emerged. Peers view phosphophyllite (Phos) as useless because it is weak and has one of the lowest hardnesses. After being given a task to establish a natural history encyclopedia, Phos approaches their distant but smart coworker Cinnabar for assistance, which kickstarts their friendship and personal development. In the meantime, the Lunarians (Moon people), who seek to profit from their luxury value, are at war with the "diamond people."