Eucalyptus oil is derived from the leaves of the eucalyptus plant and is known for its refreshing and invigorating properties. In cosmetics, it is often used for its:

1. Decongestant properties: Eucalyptus oil has decongestant properties that can help to clear sinuses and relieve congestion.
2. Antimicrobial properties: Eucalyptus oil has antimicrobial properties that can help to prevent the growth of bacteria and other microorganisms on the skin, making it useful for treating acne and other skin infections.
3. Analgesic properties: Eucalyptus oil has a cooling effect on the skin and can help to reduce pain and discomfort.
4. Aromatherapy: Eucalyptus oil has a refreshing and invigorating aroma that can help to improve mood and promote relaxation.
5. Eucalyptus oil is also used in hair care products as it is helpful in promoting hair growth, reducing dandruff, and itchy scalp.
6. Eucalyptus oil has anti-inflammatory properties that can help to reduce redness, itching, and irritation on the skin.
7. Eucalyptus oil is also used as a natural insect repellent.
8. Eucalyptus oil is generally considered safe for most skin types, but it’s always advisable to test it before applying to the face. It is important to note that eucalyptus oil is highly concentrated, and should be used in dilution with carrier oil or in small amounts in cosmetics formulations.