They discovered that smelted iron iron separated from mineral  bearing rocks called ore had impurities that gave the metal strength and hardness
तसेच, लोखंडाच्या एखाद्या हत्याराचे पाण्यात द्रुतशीतन केल्यास ते अधिक कठीण बनते हे देखील त्यांना शिकायला मिळाले.