Which one of the following minerals is a boron mineral in soils?

Correct option is B

The correct answer is (B) Colemanite

Explanation:
• Boron is an essential micronutrient for plants, required for cell wall formation and reproductive development.
• In soils, boron originates from minerals like Tourmaline (the primary source) and secondary minerals like Colemanite and Borax.
• Colemanite is a borate mineral that serves as an important source of boron in alkaline or arid environments.
• Because boron is highly soluble in the form of Boric Acid, it is easily leached in high-rainfall areas.

Information Booster:
• Boron deficiency is common in sandy soils with low organic matter.
• Indicators of boron deficiency include "hollow heart" in cauliflower and "internal cork" in apples.
• Tourmaline is a very stable mineral, so the release of boron from it through weathering is very slow.

Additional Knowledge:
• Pyrolusite (Option A): An important manganese mineral.
• Haematite (Option C): A primary iron mineral, responsible for the red color in many soils.
• Apatite (Option D): The main group of minerals providing Phosphorus to the soil; it contains Calcium and Phosphate along with Fluorine or Chlorine.