In nature, carbon is found in elemental forms as:

Explanation

To answer the question regarding the elemental forms of carbon found in nature, we can break down the information into a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding Allotropes**: Carbon exists in different forms known as allotropes. The most common allotropes of carbon are diamond and graphite.

2. **Diamond**:
- Diamond is one of the most well-known allotropes of carbon.
- It is composed entirely of carbon atoms arranged in a crystal lattice structure.
- Diamonds can be found in nature (natural diamonds) or can be synthesized in laboratories (synthetic diamonds).
- Natural diamonds are formed under high-pressure and high-temperature conditions deep within the Earth.

3. **Graphite**:
- Graphite is another common allotrope of carbon.
- It consists of carbon atoms arranged in layers, which can slide over each other, making it slippery.
- Graphite is naturally occurring and can be found in various forms, including crystalline, amorphous, and lump graphite.

4. **Conclusion**: Therefore, in nature, carbon is found in elemental forms primarily as diamond and graphite.

### Final Answer:
In nature, carbon is found in elemental forms as diamond and graphite.

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