My idea of a "green" knife is one made of recycled materials. Automotive spring steel forged into blades, and scrap wood, horse stall mat or rag mycarta scales, etc.
I made some throwing knives out of coil spring, with reground plastic scales. That plastic was good and shock proof, too.
I like recycling chain and cable into blades, too.
Hear, hear! (Or is it, "Here, here!"?)
Anyway, I like the idea of recycling old found steel. Granted, it's not like the steel I order from a supplier is made from virgin iron ore and freshly mined chromium, vanadium, etc., but picking up an old truck spring means there's one less piece of discarded crap laying around.
Plus, I like the idea of being able to work with whatcha got. I'm not likely to pick up some mystery steel, know it's constituents to the hundredth of a percent, and be able to eke out every last bit of metallurgical potential to make God's own blade...but familiarizing myself with the way steel works will allow me to do a more than passable job of making a knife, even if I'm not 100% sure of exactly what I have.
I'm also fond of domestic hardwoods for handle material. It's cheaper, and I don't have to worry that I'm going to poison myself with some weird kind of Congolese Tree Funk when I sand it.
For fuel, I use propane. I don't know if it's "better" than coal, but I find it hard to believe it isn't. And I rigged a forced-air system, which means I can achieve similar forge temps while using less gas than a Venturi system...or so I've been led to believe. (That decision was made because I'm cheap, to be honest.)
And when my quench bucket gets a little low, I take the opportunity to take a leak. Kill two birds with one stone, I say.
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