Rocks and Thier Durability

Having just been notified that the PTO will grant my request to fund the building of a statute of my favorite teacher, I am left with the task of selecting which type of rock I will use. I will have to take into account how climate, physical weathering, chemical weathering, and biological weathering will affect my statue.
I have a choice of many types of rocks to choose from including marble, granite, rock salt, chalk, limestone, and sandstone. I can easily eliminated rock salt and chalk because of how easily they erode. Rock salt, when exposed to water will start weathering immediately a…