Brazilian Rust Slate is quarried from a pit quarry in Brazil. Millions of years ago, silt and mud from a river deposited soil at the mouth of a larger body of water, giving this stone its random color variation. Water has penetrated deep into this stone through small cracks and fissures, causing the iron oxide and other minerals to oxidize. It is this process that produces the deep burgundy and gold portions of the Brazilian Rust that only exist on the surface of the stone. Even though the rust colors do not bleed all the way through the grey body of the material, this will not pose any risk to the beauty or application of the material. Brazilian slate products were formed under intense amounts of pressure, making them much more dense than other slate materials currently in the market. Arizona Tile does not recommend that Brazilian Rust Slate be installed in or near wet areas, such as showers or next to a swimming pool, because this stone has the potential to oxidize and rust. There will be noticeable variations in color and movement between pieces. Therefore, it is important and recommended that a range of this product be viewed before finalizing a purchase. As a natural stone product, it is recommended that this be sealed to extend its longevity.