Untreated metal sculptures are vulnerable to rust, especially when exposed to moisture and harsh weather conditions. However, there are several effective methods to prevent rust and preserve the beauty of your metal artwork.

1. Apply Protective Coatings: Use clear acrylic sealants, wax, or specialized rust inhibitors to create a barrier against moisture. Reapply these coatings periodically for long-term protection.

2. Control the Environment: Keep sculptures in dry, well-ventilated areas. If displayed outdoors, elevate them on stands to avoid ground moisture and provide shade to reduce exposure to rain.

3. Regular Cleaning: Remove dirt, dust, and debris with a soft brush or cloth. For stubborn grime, use mild soap and water, but ensure the sculpture dries completely afterward.

4. Use Desiccants or Silica Gel: Place moisture-absorbing materials near indoor sculptures to reduce humidity levels and prevent oxidation.

5. Inspect Frequently: Check for early signs of rust, such as discoloration or rough patches. Address minor rust spots immediately with fine steel wool or a rust converter.

By implementing these strategies, you can significantly extend the lifespan of untreated metal sculptures and maintain their aesthetic appeal.