Right there in the link: 1.4116 German molybdenum/vanadium stainless steel
It's fairly new steel, not a super duper - but this is a long, drop forged to shape fixed blade. It has to have both good finished cutting ability and workability. A really tough steel would be a pain to shape, and fixed blades don't need high hardness, they need ductility. They are used with a lot more leverage.
I bought a new Sting from AG's storeroom last summer, and I've compared it to my original with gold oak leaves. They are quite the same. The sheath that came with my new one has a molded insert, multiple webbing points, and nice straps. I much rather prefer the original with snap - which I didn't get at the time. But, AG's quite aware of that, and it was more CRKT who made the decision.
Perhaps AG could offer an exclusive sheath for his stock, hmmm?