@bungustore: Colored mechanical pencil leads have always been fragile. Pigment instead of pure graphite weakens the structure. They snap, crumble, and ghost when you erase. In 2008, Mitsubishi Pencil created Nano Dia leads by blending nano-sized diamond particles into the formula. The diamonds reduce friction so the lead glides instead of dragging, and reinforce the structure from the inside out. Up to forty percent stronger at the tip. Nothing else has come close. That formula finally fixed colored leads. Smoother. Darker. Stronger. Four hundred million diamonds in every piece.