Hi Peter! I won't go into great detail here, there is so much on the web you can go blind sorting through it. HRC refers to the Rockwell scale of hardness. 60 is about as hard as they come.There are many variables in knife manufacture; hardness, metallurgy, cold and heat treatment, sheer size and method of manufacture ( forged, cast, stock removal.) All can effect the quality plus or minus No, there is no standard for marine knives, or any other for that matter. A "marine steel"' is like the mythical surgical steel, there isn't any. Obviously you want a stain-or rust resistant knife, which is what stainless is-resistant. What is allowable under the new knife laws in OZ? The classic sheepsfoot was regulated onto ships to keep sailors from killing each other. Obviously this isn't very effective on great whites , but nothing less than a harpoon is. Are you allowed "bang sticks" over there ( a shotgun shell on a short baton?)