Metals used and are known by people during rig vedic culture are given below.
According to Jainism there are five instruments of Knowledge.
Name of rivers that were mentioned in Rig Veda. List of rivers that were mentioned in Rig Veda.
There are six systems in Hindu Philosophy. These systems are given by six famous philosophers of Ancient India.
Upavedas are applied knowledge and traditional literature which contain the subjects of certain technical works. There are Four Upavedas.
Vedangs are the limbs of the Vedas. These are the treaties of Science and Arts. There are Six Vedas.