Mapping Mineral Wealth — Pierre Berthier
Pierre Berthier discovered and mapped valuable mineral deposits throughout France. Perhaps the most important of these were mineral sources of phosphate. Berthier’s work was focused on identifying the mineral content of rocks. As a young mining engineer, he traveled throughout France identifying and mapping ore deposits ranging from aluminum to zinc. It was Berthier who identified the naturally-occurring mineral that became the major source of aluminum, which he found near the village of Les Baux-de-Provence in the south of France and named bauxite.
Later, Berthier became interested in what accounts for the mineral content of plants. Berthier found that the mineral composition of the ash left over when plant matter is burned is different from the composition in either the soil or the water. Before this, people thought that the minerals found in the ash left from the combustion of plant matter were either from soil residue stuck to the outside of the plants or minerals carried in water that happen to be taken up by the plant. Apparently, plants were taking up some mineral selectively and excluding others. In essence, plants mine the soil for the minerals that are useful to them. By analyzing ash from a number of different plants, Berthier identified phosphate as an essential nutrient and an important fertilizer.
Pierre Berthier is one of the 72 scientists and engineers named on the Eiffel Tower.
