Question

Olivine is a good source of:

• A. Mg
• B. Mn
• C. B
• D. OL

Hint:

Match soil nutrients with their primary mineral sources for exams:
- Magnesium (Mg) \(\rightarrow\) Olivine, Dolomite, Biotite.
- Boron (B) \(\rightarrow\) Tourmaline (highly stable mineral).
- Potassium (K) \(\rightarrow\) Feldspars, Orthoclase, Muscovite.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Soil minerals are the primary source of essential plant nutrients released through physical and chemical weathering.
Minerals are classified based on their crystal structures and chemical compositions.

Step 3: Detailed Explanation:
Olivine is a group of magnesium iron silicate minerals with the chemical formula:
\[ (\text{Mg, Fe})_2\text{SiO}_4 \] - It is a primary silicate mineral commonly found in mafic and ultramafic igneous rocks (such as basalt and peridotite).
- In this mineral, magnesium (Mg) and iron (Fe) ions substitute for each other within the crystal lattice.
- Olivine represents a continuous solid-solution series between the magnesium-rich endmember, forsterite (Mg$_2$SiO$_4$), and the iron-rich endmember, fayalite (Fe$_2$SiO$_4$).
- During soil chemical weathering, olivine is highly unstable and breaks down easily, releasing large amounts of Magnesium (Mg) and iron into the soil solution.
- Thus, it serves as an excellent natural mineral source of magnesium, an essential macronutrient required for chlorophyll synthesis in plants.
- Let us analyze the other options:
- Manganese (Mn) is sourced from minerals like pyrolusite.
- Boron (B) is sourced from tourmaline.
- Option (D) "OL" is a distractor and not a chemical element.
Therefore, olivine is a primary source of magnesium.

Step 4: Final Answer:
Olivine is a rich mineral source of Magnesium (Mg), matching Option (A).