Complex sentence: There are several ancient Tamil, Greek, Chinese and Roman literary references to high carbon Indian steel since the time of Alexander's India Campaign or over two millennia, it was the most advanced material known to mankind, with superplasticity and complex microstructure.
Split into simpler sentences: There are several ancient Tamil, Greek, Chinese and Roman literary references to high carbon Indian steel since the time of. For over two millennia, it was the most advanced material known to mankind, with and complex microstructure.