Billipp Knives are hand-forged from 52100 high-carbon steel. Because the blade is not stainless, and therefore can rust, it will require maintenance. Never let the knife soak in water, as this can damage both the steel and the wooden handle, and of course don't ever put it in the dishwasher. My routine is to wash the knife gently with soap and water as soon as I'm done using it, and then immediately dry it off with a clean dish towel.
Before long the steel will darken. This is normal as the acids in food start to stain the blade, and will become less drastic as the blade begins to develop a patina. To avoid heavy staining of the blade, keep the knife as clean as possible while you use it, wiping off the juice from fruits and vegetables as you go.
Occasionally, or if the knife going to be stored for a while, wipe the blade and handle down with mineral oil (food safe and available in CVS under laxatives), rubbing the oil into the handle. This will keep the blade from rusting and the handle from drying out or absorbing food juice.
All my knives are rigorously tested before completion, and do not leave my shop without my full confidence. If you ever experience a problem with your knife or have a question about its care, please do not hesitate to contact me.
Enjoy!