<https://s.mj.run/JHpkbf0-heU> Create a set of 7 cartoonish, colorful mineral illustrations for a 2D casual mobile game. Each mineral progressively looks more refined and valuable, in simple, clean, and playful art style. Basic black coal rock, rough and matte. Dark brown stone, smoother and less jagged. Small red crystal cluster, slightly shiny and vibrant. Simple green crystal with slight translucence. Blue crystal with basic glow effects, simple shape. Purple-blue crystal, more polished, gentle light reflection. Large bright blue gemstone, shiny but minimal details, png image, white background --niji 6