Also, regarding orange and not being lost I'd just like to point out a couple things.....

First, you should never set a knife down in the field as its far too easy to lose even with bright colors. Always put it back in it's 'home' when you're done with it, even if you'll need it again soon.

Second, Fluorescent colors like orange and such will do you no good if your knife gets covered with debris such as leaves. I've been present when a bright yellow GPS unit was dropped on the way to the deer stand, we will never see that GPS again as Michigan woods are loaded with leaf litter.