Morihei Hishiboshi Karasu Whetstone #12000 Razor

This is a stainless steel knife. It becomes stainless due to a certain amount (10-13%) of chromium and/or nickel in the alloy, it forms a film layer which acts as a barrier between metal and oxygen. Stainless steel is easy, practical and functional but not completely maintenance free. With very bad maintenance it can rust or show pitting, after all it’s called stainless not stain-free steel. The corrosion resistance varies with each stainless steel. In my opinion the same rules apply here as with carbon steel (non-stainless).

Store your knife dry and clean, never let it air-dry after washing, no dishwasher and avoid extremely hard products like frozen foods or bones ect. But a big difference to carbon steel is that your margin of error is much bigger, the rust resistance is much greater and thus easier and more worry free to maintain.

Please note that there are many different stainless steels, just like carbon steels, each with its own properties and characteristics. Each should be judged individually.