Graphite is

Options

A. harder than diamond
B. used as a lubricant
C. an amorphous allotropic form of carbon
D. oil like substance

Explanation

### Step-by-Step Solution:

1. **Identify the Nature of Graphite**:
- Graphite is an allotrope of carbon. Allotropes are different forms of the same element, where the atoms are bonded together in different ways.

2. **Determine the Structure of Graphite**:
- Graphite has a crystalline structure. It consists of layers of hexagonal (six-membered) carbon atom arrangements. Each layer is made up of interconnected hexagonal rings.

3. **Understand the Bonding in Graphite**:
- The carbon atoms in each layer are bonded by strong covalent bonds, while the layers themselves are held together by weak Van der Waals forces. This weak bonding between layers allows them to slide over each other easily.

4. **Properties of Graphite**:
- Due to its layered structure and the weak forces between layers, graphite is soft and can be used as a lubricant. This property makes it useful in various applications, such as in pencils and as a lubricant in machinery.

5. **Comparison with Other Allotropes**:
- Unlike diamond, which is another allotrope of carbon, graphite is much softer. Diamond has a tetrahedral structure that makes it extremely hard.

6. **Conclusion**:
- Therefore, the correct statements about graphite are:
- It is a crystalline allotrope of carbon.
- It can be used as a lubricant due to its layered structure.
- It is softer than diamond.