White crystal semiprecious stone, also known as quartz crystal, is commonly used in various interior design applications such as countertops, backsplashes, and decorative accents. However, its suitability for exterior applications in very rainy climates needs careful consideration.

Quartz crystal is generally durable and resistant to environmental factors such as UV radiation and temperature changes. However, prolonged exposure to excessive moisture, freeze-thaw cycles, and heavy rainfall may affect its stability and lead to potential issues.

In very rainy climates, constant exposure to moisture can promote the growth of algae, mold, and mildew on the stone surface, causing discoloration and staining. Additionally, freeze-thaw cycles can cause the stone to crack or chip over time.

To ensure the longevity and performance of quartz crystal in exterior applications in very rainy climates, consider the following factors:

1. Quality and Grade: Choose a high-quality quartz crystal stone that is specifically rated for outdoor use and can withstand exposure to moisture and weather conditions.

2. Moisture Protection: Ensure proper installation and sealing of the stone to minimize water absorption. Regularly maintain and re-seal the stone as recommended by the manufacturer to prevent moisture penetration.

3. Drainage: Ensure adequate drainage around the stone application to prevent the pooling of water and reduce the risk of water damage.

4. Cleaning and Maintenance: Regularly clean and dry the stone surface to prevent the buildup of algae, mold, and mildew. Use gentle, non-abrasive cleaners recommended by the manufacturer.

5. Temperature Considerations: If the climate experiences extreme temperature fluctuations, such as freezing temperatures, consult with a professional to ensure the stone is suitable for those conditions.

Overall, while quartz crystal can be used in exterior applications in rainy climates, proper installation, sealing, drainage, and maintenance are crucial to its long-term durability and appearance. It is advisable to consult with a stone supplier or professional installer who can provide specific recommendations based on the stones properties and the local climate conditions.