Thanks so much. I wanted to give the oil suggestion a try for a few days and then reply back. I cleaned the diamond stones as usual “warm soapy water, an old disposable electric toothbrush”, dried the stones with a towel and applied my favorite oil (ballistol). The Ballistol immediately pulled up a bunch of gunk from the diamond stones that the soap, water and toothbrush did not get. In fact,
It was like I had not cleaned the stones at all giving the amount of gunk that came out of the stones.
I washed the gunk out, dried the stones again and applied another light coat of oil. I have had no rust issues since using your suggestion of the oil and it has not affected the performance of the stones. I like to use Ballistol because it is not toxic to humans and many of the knives I sharpen are kitchen knives.
Thanks so much for the help, I truly appreciate it and perhaps this will help others with the same issue.
Dan…