Mata'a Obsidian Blade

A mata'a, the stemmed obsidian blade of Rapa Nui: a glossy black obsidian flake about 10 cm long with a broad, roughly triangular faceted blade and a narrow tang. Knob: haft none or hafted (the tang bound to a short wooden shaft with bark fibre). Lies on y=0.

风格：low-poly, flat-shaded vertex colors, no textures, 2 materials: the shared opaque one plus a distinct surface (glass, water or chrome), which stays its own mesh through mergeAssets rather than merging into the rest; shares palette and scale with its kit