I'll put a number on it: .002g; those are the smallest ones I've detected with my GB2 and the GM can easily "hear" them at a distance of 1" with the small coil. My scale only weighs with an accuracy of .002g. So it could be even smaller than .002. Anyway, I totally agree. The GM is a marvelous piece of equipment to complement a big game hunter like the 7000. Great job, Bill!!
You may wish to start your own post on the topic. If you are serious about learning why meteorites do not cause fires and why the fires is Wisconsin, Chicago, and in Michigan were unrelated to each other and could not have been started by a meteorite fall, then private message me.