Precious stones, such as gem stones, are products of

Options

A. Volcanic rocks
B. Sedimentary rocks
C. Metamorphic rocks
D. Igneous rocks.

Answer

**Step-by-Step Solution:**

1. **Understanding Gemstones**: Begin by defining what gemstones are. Gemstones, also known as precious stones or jewels, are pieces of mineral crystals that are cut and polished for use in jewelry and other decorative items.

2. **Formation of Gemstones**: Recognize that gemstones are formed from specific types of rocks. The formation process involves the crystallization of minerals under certain conditions.

3. **Types of Rocks**: Identify the types of rocks mentioned in the question: volcanic rocks, sedimentary rocks, metamorphic rocks, and igneous rocks.

4. **Identifying the Correct Rock Type**:
- **Volcanic Rocks**: These are formed from lava that cools on the Earth's surface. While some minerals can be found in volcanic rocks, they are not the primary source of gemstones.
- **Sedimentary Rocks**: These are formed from the accumulation of sediments. They typically do not contain gemstones.
- **Metamorphic Rocks**: These are formed from existing rocks that have been transformed by heat and pressure. Some gemstones can be found in metamorphic rocks, but they are not the primary source.
- **Igneous Rocks**: These rocks are formed from the cooling and solidification of magma or lava. Many gemstones, such as diamonds and emeralds, are formed from minerals that crystallize within igneous rocks.

5. **Conclusion**: Based on the above analysis, gemstones are primarily products of igneous rocks due to the conditions under which they form. Therefore, the correct answer is **igneous rocks**.

**Final Answer**: Precious stones, such as gemstones, are products of **igneous rocks**.

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