philosophers' stone

It was only natural in that century that he should turn his thoughts toward alchemy and the philosophers stone.

And though a man be poor, yet may he very well attain unto it, and may be employed to make the Philosophers Stone.

Secondly, of the Philosophers Stone, what is meant by it, and whether by means thereof true Gold can be produced?

Fourthly, what the celebrated Philosophers Stone was among the Ancients, and what they understood by the same?

A rich and well-stored mind is the only true philosophers stone, extracting pure gold from all the base material around.