In the book they talk of many things, one is the dicovery by a Dr. Julius Hensel that milled stone (such as granite) is the only soil ammendment needed for truly organic plants which can be flavourful and healthy in all respects.

I will put in a small exert then a link at the end.

"Julius Hensel's pioneer work in opposing the use of chemicals in agriculture,
a half a century later, found rebirth in the Organic Movement
which has swept through the world. But Hensel is more modern than the
most modern agricultural reformer, for he claimed, on the basis of theoretical
chemical considerations, and supported by practical tests, that his
Stone Meal can replace not only chemical fertilizers but all animal ones
as well.
It was the German agricultural chemist Liebig who first put forward the
phosphorus-potash-nitrogen theory of chemical fertilization. This false
doctrine Hensel bitterly attacked and in so doing, won the ire of the financial
interests behind the sale of chemical fertilizers, which used agricultural
authorities and university professors to denounce poor Hensel as a
charlatan and his Stone Meal as worthless.
Though his fight against chemical fertilizers was a losing battle and he
died as a defeated hero, it took a generation for Hensel's efforts to bear
fruit in the modern Organic Movement, which has not given its founder
the credit due him."

http://www.scribd.com/doc/30990143/Suppressed-Inventions-and-Other-Dis coveries

Page 227 of the book and 235 in the Adobe reader.

The book is a not bad read if you are interested in that hide and seek. The establishment sure seems to hide a lot of things from the common man.

Translated from German - 1894.

http://www.soilandhealth.org/01aglibrary/010173.hensel.pdf

For example, limestone rocks are rich in calcium. Granite rocks are rich in potassium, etc. Seaweeds of course are the king of micronutrient fertilizers and soil amendments. There can be up to 70+ trace elements in seaweed. In locations where seaweed is not readily available; rock powders is one answer to the problem.

Research continues to reveal that insoluble tiny particles like rock powder minerals, can be easily digested or absorbed via microbial activity, over time, into the anatomy of growing plants, thriving in the presence of rich organic compost, and other forms of powerful biostimulants like aerobic compost teas.