Friend was in his garden it was raining green stones landed on the ground from the sky, very smooth green, and

Question

glow in the dark. what are they and where did they come from

Answer 1

what can actually happen in some occasions is bad weather like a tornado etc can suck up animals/objects, in this occasion, the green stones and then transport them across distances and deposit them as rain, is that or, an alien just shat on your friend

Answer 2

Where did they come from? A bad acid trip, it sounds like.  

Answer 3

Wow - Kriptonite!!!  Where abouts in Metropolis do you live?

Answer 4

Some types of algae (slime) are green and fluoresce in the dark.

PS - DON'T EAT THE YELLOW SNOW :-)

Answer 5

What was your friend smoking, sounds good.

Answer 6

they sound radioactive, don't go near them! unless you want cancer..

Answer 7

Spooky.

If this is remotely true, he needs to send them to a geologist asap.

Answer 8

the sky you said

Answer 9

They're from krypton and i want them back.

Answer 10

The stones were picked up by a strong weather disturbance an transported to the area above your friends yard. The same thing happened to me on a golf course, frozen grubs began falling onto the putting green, it was weird.