A series of 7 distinct mineral illustrations in a colorful, cartoonish style, perfect for a 2D casual mobile game. Progress visually from a rough coal rock to an exquisite blue gemstone crystal, each stage increasingly detailed and beautiful. Stage descriptions: Simple rough black coal, matte and basic. Dark brown rock, smoother texture, slightly shinier. Bright reddish mineral, small sharp edges, subtle shine. Green translucent crystal with moderate clarity. Polished deep blue crystal glowing faintly with magical sparkles. Gradient purple and blue crystal with vibrant light reflection. A large, luxurious sapphire-blue crystal, bright glowing light effects, majestic and visually striking. Flat 2D digital art style, casual, clean, and vibrant colors, suitable for mobile games. Each mineral should appear distinct yet consistent in style., pn --niji 6