Desert Grey Calcarenite, also known as Tucson Grey, is a type of limestone found in the United States. While it is generally suitable for exterior applications, its performance in very rainy climates may vary.

Limestone is a porous material, meaning it can absorb water. In very rainy climates, where heavy rainfall and prolonged exposure to moisture is common, the limestone may be more susceptible to water damage. Excessive moisture can lead to staining, erosion, and the growth of algae or mold on the surface of the stone.

To mitigate these risks, it is important to select a variety of Desert Grey Calcarenite that has been specifically tested and approved for exterior use. Additionally, proper installation techniques, such as sealing the stone and using appropriate drainage systems, can help protect the limestone from excessive water absorption.

Regular maintenance and upkeep, including regular cleaning and resealing, will be necessary to ensure the longevity and performance of the limestone in very rainy climates. Consulting with a professional stone supplier or installer knowledgeable about regional conditions can provide more specific advice and guidance regarding the suitability of Desert Grey Calcarenite for your particular location.