Originally Posted by
Zephyr
You can get most necessary work done on a 1K stone, but for razors tha have bad chipping, frowns etc. a lower grit stone is helpful, many use the 325 DMT, personally I don't fancy the sound and feel of a razor on a steel plate and use a Shapton Pro 320.
When that is said, have you honed razors before? I wouldn't recommend jumping straight into blade/edge restoration without having the basic honing in place.
As for figuring out the aprox grit of an unknown stone you can take a spoon and run it a few strokes on the stone and compare the scratch pattern to other spoons ypu've done the same with, only on different stones of a known grit.
It's not 100% accurate, but you should get the aprox grit.