As above, Solingen steel originates in Solingen, Germany. There are a number of steels given that name. Puma seems to be using mainly D 1.4116 stainless in a lot of their current knives. It's about the equivalent to 420HC, as used by Buck and others. The solingen carbon steels are ok, but they tend to harden to lower Rc's then what we use in the States. The overall quality of their knives is quite good, but as far as I'm concerned they're way over priced for the materials they use.