First of all, thanks for sharing this.
I don't understand how the pond could have been emptied, the rock is not big enough to evaporate a large amount of water, even if it was at 3000ยบ
Celsius.
I also don't understand how a meteorite could hit the pond and not get buried on the bottom.
Another thing, did the rock stuck to the bathroom scale? If it is magnetic or has some magnetic properties it should have stuck to the scale in the
same way the ring stuck to the rock.
And was the rock humming when you first saw it on the pond?
These are all my questions for now, but I suppose we will never get answers for most of them.
Now for my opinions.
First, take new photos, please, those are all out of focus, and it's a shame to have such a rock and not have decent photos.
The green also reminded me of copper, and the magnetic effect can affect non-magnetic materials if they are electrical conductors and if the rock has
a non-constant magnetic field; a changing magnetic field would created electrical currents on conductive materials and those currents would create a
magnetic field.
If it's not hot it probably is not radioactive, at least much radioactive.
You may know its volume by filling some container with a scale on it to the top and put the rock inside it tied to a string. After the rock enters the
water you can pull the rock back out of the water and see how much water went over the rim, that would be the volume of the rock. If you could weight
it you could know the density.
If you could do these things it would be great, it would give us more information.