A circular ancient elemental emblem divided into four equal 90-degree quadrants. Design ONLY the Earth quadrant (bottom left section). The Earth section should contain cracked stone texture, moss, small glowing green veins, and embedded crystal shards. The rest of the circle should be clean placeholder surface with minimal detail. The emblem should have slight thickness like a medallion, flat back surface, game-ready topology, clean edges between quadrants, centered pivot, highly detailed PBR textures, fantasy style, 3D model, GLB export friendly.