Which of the following is an example of chain silicates?

Options

A. Kaolinite
B. Zircon
C. Benitonite
D. Diopside

Explanation

To solve the question "Which of the following is an example of chain silicates?", we need to analyze the options provided and identify which one corresponds to the definition of chain silicates.

### Step-by-Step Solution:

1. **Understand Chain Silicates**:
- Chain silicates, also known as enosilicates, consist of silicate tetrahedra linked together in a chain-like structure.
- The basic unit of chain silicates is represented by the formula \( \text{SiO}_3^{2-} \) for single chains, with a silicon-to-oxygen ratio of 1:3.

2. **Examine the Options**:
- We will analyze each option provided to determine if it fits the definition of chain silicates.

3. **Option 1: Kaolinite**:
- Formula: \( \text{Al}_2\text{O}_3 \cdot 2\text{SiO}_2 \cdot 2\text{H}_2\text{O} \)
- Structure: It has an octahedral layer structure and contains alumina.
- Conclusion: Kaolinite is not a chain silicate.

4. **Option 2: Zircon**:
- Formula: \( \text{ZrSiO}_4 \)
- Classification: It belongs to the orthosilicate group.
- Conclusion: Zircon is not a chain silicate.

5. **Option 3: Bentonite**:
- Description: A rare blue barium titanium cyclosilicate.
- Classification: It belongs to the category of cyclosilicates.
- Conclusion: Bentonite is not a chain silicate.

6. **Option 4: Diopside**:
- Formula: \( \text{CaMgSi}_2\text{O}_6 \)
- Classification: Diopside is a pyroxene mineral and is known to be a chain silicate.
- Conclusion: Diopside is indeed an example of a chain silicate.

7. **Final Answer**:
- The correct answer is **Diopside**.