There are 2 ways to enduring wealth through all of history;
1. Take a seed and use the resources already in the earth/Nature to multiply it exponentially and it keeps generating money even while you sleep, enlarging astronomically as time ages it.
Or
2. Create a "Cycle"/system that takes a particular waste product (e.g. words, urine, rubber, plastic, sleep, books, clothes, time, money, water) and makes it useful again for humanity, generating wealth even while you sleep, as long as humanity produces it as a waste.