the.com/obsidianite

means A purported or informally named mineral derived from or resembling obsidian, whose status as a distinct, recognized mineral species is dubious or unestablished.

from Built on "obsidian," the glassy volcanic rock, plus the suffix "-ite," the standard tail geologists pin to minerals and rocks (from Greek "-ites," "belonging to"). Obsidian itself carries a curious tale: the Roman naturalist Pliny the Elder wrote of "obsianus lapis," a dark stone said to be found by one Obsius in Ethiopia — and a later copying slip is thought to have turned "obsianus" into "obsidianus," the spelling that stuck. So the parent name may rest on a scribe's stumble, and the "-ite" simply dresses it up in mineral's clothing.