Do I need to use special diamonds to refinish granite, can I use the same diamonds I use on marble?

This will depend on what diamonds you purchase. There are special diamonds deigned for granite and there are companies who make diamonds that will work on both marble and granite. I have found that the special diamonds perform much better than the combination sets.

TIP Before purchasing a set of diamonds for granite, ask the supplier to perform a demonstration. I would also check with other craftsman and ask them which diamonds they prefer.