A mineral spa is a special kind of hot tub filled with special water that has minerals in it. These minerals can come from the ground or from the ocean, and they can be good for your skin and your body. When you go to a mineral spa, you get to soak in the warm water and relax your muscles. It feels really good! Some people also believe that the minerals in the water can help alleviate certain health problems, like arthritis or skin conditions. So when you go to a mineral spa, not only do you get to have fun, but you might also be doing something good for your body.