Yes, Brazils Mary Black Granite can be used for exterior applications in very dusty climates. Granite is a highly durable and resilient natural stone that can withstand various weather conditions, including dusty environments. Its dense composition and low porosity make it resistant to moisture, stains, and dust accumulation. However, it is important to properly seal the granite to enhance its resistance to external factors and maintain its appearance over time. It is recommended to consult with professionals or granite suppliers to determine the most appropriate sealants and care instructions for your specific application and location.