What makes a knife suitable for the rigors of a survival lifestyle? Let’s start with blade material.
The blade of a good survival knife should be made of tough, edge-holding, corrosion-resistant metal. Knife metallurgy is a constantly evolving science, but in general, a stainless steel blade in any one of the 440 A, 440 B or 440 C categories will be a good choice.
When it comes to blade geometry, the knife should have a full-length tang that runs all the way to a functional pommel at the butt of the handle that can serve as a hammer. Some part of the blade should have aggressive serration for sawing through small limbs. The back of the blade should have a stout spine that can be hammered on to assist in chores like splitting firewood into kindling or hacking your way through a tree limb. The blade should have a sharp point and good slicing ability. Strive for some balance between the amount of the blade that is serrated and the portion that has a plain edge, because you’ll need both.
Under survival conditions, you’ll sometimes be wet and muddy. Your knife needs a grip that is not slippery when wet. Knife manufacturers use every trick in the book to accomplish this, from shaping the grip with contours to fit among your fingers, to using aggressive crosschecking, or employing “grippy” materials. Find a knife that feels comfortable in your hand, and do a wet test, if possible. The grip should be durable enough to take a pounding without falling apart in your hands. A pretty grip that shatters the first time you use the knife as an axe isn’t worth much.
Your knife should be big enough and heavy enough to serve as an axe, pry bar, or a digging tool. Ideally, you’ll use your blade to make a good digging stick out of wood, so you don’t abuse your knife by sticking the blade in the ground. But you never know what’s going to come up in a survival situation, and the knife shouldn’t be a wimp about it.
If you pay attention to those four characteristics — blade material, blade geometry, grip, and overall size, you should be able to find a good survival knife that will suit your needs.