Oxide ore are purified by levigation process.

Answer

**Step-by-Step Solution:**

1. **Understanding the Levigation Process:**
- Levigation, also known as hydraulic washing or gravity separation, is a method used to separate ore from impurities based on differences in density.

2. **Application of Levigation:**
- This process is primarily used for the purification of oxide ores and carbonate ores. The technique involves washing the ore in a current of water, which allows lighter gangue particles to be washed away, leaving behind the heavier ore particles.

3. **Mechanism of Separation:**
- The separation occurs because the gangue particles have a lower density compared to the ore particles. When water is used, the lighter gangue is carried away, while the denser ore remains.

4. **Conclusion:**
- Given that levigation is indeed used for the purification of oxide ores, the statement "Oxide ore are purified by levigation process" is true.

**Final Answer:**
- True, oxide ores are purified by the levigation process.

---