Yes, Alexandra Brown Schist can be used for exterior applications in very windy climates. Schist is a strong and durable natural stone that has been used for centuries in construction and landscaping. It has excellent weather resistance and can withstand the impact of strong winds without any issues. However, it is always recommended to consult with a local expert or architect to ensure that the specific installation and design considerations are taken into account for the best outcome in windy climates.