What mineral is used to make a saw blade?

Maybe you mean element instead of mineral? If that's the case, knife steel is composed of a variety of elements to achieve specific characteristics for the knife. Some common elements in quality cutlery steel are:

-chromium

-molybdenum

-vanadium

-manganese

-carbon

other elements are used as well but these are just a few of the "core" elements that are more commonly found. As an example, steel with a higher carbon content will be tougher and less prone to chipping however it will corrode faster than a more "stainless" steel. If you have a blade with a high nitrogen content, the knife will be very resistant to corrosion but may not be quite as tough.