Polished bronze sculptures are admired for their lustrous finish, but over time, their surfaces often lose shine and become dull. Understanding the causes of this dulling can help in preserving these artworks.

1. Oxidation and Patina Formation: Bronze reacts with oxygen and moisture, forming a patina. While some patinas are desirable, excessive oxidation can lead to unsightly dullness.

2. Environmental Pollutants: Exposure to sulfur compounds, salt air, or industrial pollutants accelerates tarnishing, especially in urban or coastal areas.

3. Humidity and Moisture: High humidity levels cause bronze to corrode faster, leading to surface degradation.

4. Improper Cleaning Techniques: Harsh chemicals or abrasive cleaners strip protective coatings, making the bronze prone to dulling.

5. Lack of Protective Coatings: Without wax or lacquer, bronze is vulnerable to environmental damage.

To maintain brilliance, regular cleaning with gentle solutions and applying protective coatings is essential. By addressing these factors, the longevity and beauty of bronze sculptures can be preserved.