While working in a coal mine, Farha's father found a piece of coal, which he brought back home. It was very hard and had a metallic lustre. Which type of coal could this be?

Options

A. Peat
B. Lignite
C. Anthracite
D. Bituminous coal

Answer

To determine the type of coal that Farha's father found, we need to analyze the characteristics of the coal mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Characteristics of the Coal**: The piece of coal found by Farha's father is described as "very hard" and having a "metallic luster".

2. **Understand Different Types of Coal**: There are several types of coal, including:
- **Peat**: This is the earliest stage of coal formation, is soft, and does not have a metallic luster.
- **Lignite**: This is also known as brown coal, is soft, and has a low carbon content. It does not exhibit a metallic luster.
- **Bituminous Coal**: This type is harder than lignite and has some luster, but it is not as hard as anthracite.
- **Anthracite**: This is the hardest type of coal, has a high carbon content, and is known for its shiny, metallic luster.

3. **Compare the Characteristics**:
- Since the coal found is "very hard", it rules out peat and lignite.
- Bituminous coal is harder than lignite but not as hard as anthracite and does not typically have a metallic luster.
- Anthracite, on the other hand, is both very hard and has a metallic luster.

4. **Conclusion**: Based on the characteristics described, the piece of coal that Farha's father found is most likely **anthracite** coal.

### Final Answer:
The type of coal that Farha's father found is **anthracite**.