Catania Limestone is a type of limestone that originates from Sicily, Italy. Limestone in general is known for its durability and suitability for exterior applications. However, when it comes to very dusty climates, there are a few factors to consider:

1. Porosity: Limestone is a porous material, which means it can absorb moisture, dust, and other particles from the environment. In dusty climates, this can cause the limestone to retain dust and dirt, which may require frequent cleaning and maintenance.

2. Weathering: Limestone can be affected by weathering processes, including erosion and the deposition of dust particles on its surface. In very dusty climates, the accumulation of dust on the limestone can accelerate weathering, leading to a more aged or worn appearance over time.

3. Cleaning and maintenance: To maintain the appearance of limestone in very dusty climates, regular cleaning will be necessary. This may involve pressure washing, using mild detergents, or other cleaning methods suitable for limestone. The frequency of cleaning will depend on the dust levels and the aesthetic preferences of the owner.

In summary, while Catania Limestone can be used for exterior applications in very dusty climates, it is important to consider the porosity, weathering, and maintenance requirements associated with this material. Regular cleaning and maintenance will be necessary to ensure its longevity and appearance. Consulting with a professional stone supplier or installer can provide more specific advice based on the unique climate conditions and specific use case.