So, before testing the blade for its hardness, a last cleaning and minor sharpening is useful

A regular steel rod is used for the test (a nail would do as well)

Aiming and hitting the blade onto the rod without hesitation -

- and a second time to ensure the goal is attained.

Having a look at the damaged rod.

And with the help of the test piece, feeling if the sharp edge itself did withstand the hit, or if it was damaged - if dented, it would mean that the blade is too weak to be released.

This one passed the test and is accepted, the customer, who is present at the time, may convince himself.

Having a closer look

See the notch?!

One may clearly see the efficient dept of the cuts

Remarkable! And the blade doesn't show even a slight scratch, it's good to go to the next stage.