I think MANY are fake. Just because some guy or group claim to have made them before, doesn't mean they made them all. Many crop circles are found to be hoaxes when investigators do their research. The circles that are still considered mysteries (nobody can really say where they come from) have numerous qualities yet to be faked. Stalks are bent and NOT broken is probably the one that everyone needs to remember. When hoaxers use strings and boards they BREAK the crop and push it down. The bonafide mystery circles seem to have actually steamed the stalked and softened it somehow in order to bend it without breaking. Their are also traces of of an iron (or some other metal) alloy in very small particles all over the crop circles, which are NOT in the rest of the crop. I saw a show where they had a bunch of MIT students try to duplicate all these qualities, but the particles they were able to put down were NOT as uniform and were easily distinguishable from the real thing (they built a gun that looked like a flame thrower). They also couldn't get around the part that when they smashed the crop they tended to break the stalks. Interesting stuff. I still believe the majority of crop circles are hoaxes.
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