Fertilizer is a multitude of chemicals. The basic ones are what they call NPK fertilizers. But what agriculturalists understand as they've learned more is that there are also micronutrients that are important in fertilizers. Zinc is one of them, and barium is another one. I'm not a soil scientist, but I think there are other components that are often added.
Today in India there is a very extensive program of adding zinc and other micronutrients to fertilizers. I think there are something like eight or ten different fertilizer companies in India that are selling zinc-enriched fertilizers.