Many times harder than conventional steel blades, the new zirconium oxide blades used by Stone River Knives are so durable that they rarely ever need sharpening.
When it comes to knife-edge maintenance, most folks see it as the worst from of drudgery. Indeed, sharpening a knife is time consuming and often frustrating. A friend of mine hates dealing with the whole matter, so he just purchases a brand new knife every time he goes hunting. That’s certainly one way of handling the situation, albeit an expensive one! Another approach to cut down on the amount of time you spend involved in blade edge maintenance is to use a knife with extremely hard blade material.
Interestingly, the hardest material known to man is diamond, rated 10 Mohs on the Mohs mineral hardness scale (conceived in 1812 by the German Mineralogist Frederich Mohs). Of course it would be impractical to create a knife blade from such a rare mineral. The various steels used in conventional knife blades score about 4.5 Mohs, which is hard enough to provide adequate cutting service. However, another material, zirconium oxide ceramic measures 8.5 Mohs, thereby far exceeding the hardness of conventional steel and is currently used to produce knife blades that provide superior cutting service without the negative aspect of repeated edge maintenance.
A process called hot isostatic pressing (a molding process) is utilized to form knife blades from zirconium oxide ceramic composites. This process can be used to produce finished blades of various sizes and patterns, without the need for secondary profiling. The upside is that the resulting blades are extremely hard and so durable that they rarely need sharpening. The downside is that ceramic blades are somewhat brittle and will fracture if dropped on a hard surface, or when lateral pressure is applied (bending, twisting). Despite those negative aspects of zirconium oxide ceramic as a knife blade material, when used for straight cutting, its performance has few rivals.
Stone River Knives makes two different fixed-blade hunting knives with blades crafted from zirconium oxide ceramic. Their first entry is a Change-Blade knife that features two 3 1/2-inch, white zirconium oxide ceramic drop-point pattern blades and an identical companion AUS-8 stainless blade, both of which easily slip into a single G-10 locking handle. A formed nylon sheath conveniently holds both the knife and the two additional blades. You might ask: Why both types of blades? The simple answer is that the ceramic blade (the extra blade is provided in case of accidental blade damage) can make short work of all of the straight cutting chores when dealing with tough hide and muscle tissue; while the stainless blade is fully able to handle the heavy duty work of splitting joints, cutting against bone and light prying often involved in field butchery. Priced at $149.95, this knife offers the best of both blade edge retention (ceramic) and toughness (stainless steel) in a single exchange blade package.
The other Stone River knife that caught my eye was their new fixed-blade Ceramic Hunting Knife. Featuring a 3-inch, full-length tang, black zirconium oxide drop-point pattern blade, along with a handsome stag handle insert and an attached nylon lanyard. This is perfect cutting tool for basic field dressing and skinning. Best of all, the knife is completely rustproof and seldom needs sharpening. A formed nylon sheath is also provided for safe and convenient carrying when in the field. Priced at $99.95, this particular knife can solve all of the need for constant edge maintenance, now and in the near future.
I’ve used Stone River ceramic knives on deer, antelope and wild hogs with great success. Because my knife use doesn’t exceed the parameters of the ceramic blade material, there hasn’t been any inadvertent blade breakage. What I have experienced is a level of blade edge retention that has few parallels. When the same blade (without any sharpening) was used to field dress and skin three boar hogs during a recent hunt, my companions where really impressed with blade performance.–Durwood Hollis