UFO Sighting in Detroit, Michigan on April 30th 1975 – They were bright orb like, each was a different, solid color. I have never seen anything like them before or since!

I was a young child when I experienced this, I was not a very imaginative child and did not make things up or exaggerate. I can't tell you the exact year except that it had to be in the mid to late 1970's and the time was anywhere from 10 p.m. to 11 p.m. I was supposed to be in bed asleep but, I tossed and turned and could not go to sleep, so I got out of bed and went over to my window to look out. What I saw has stayed with me all these years, it may not sound like anything to some people but for me it totally astounded me! My bedroom was on the main floor of the house and out my window I could see our backyard, the alley and the yard and house behind us as well as a good view of their front yard tree. In that tree I saw orbs that were solid and varied in color, they did not change color but this tree was full of them and they were zipping about the tree and the speed at which they were going around this tree was amazing. This went on for a few minutes and I was totally mesmerized and when it all ended I think they just vanished. I know this was not some laser light because they were solid. The next day, I went into the ally to see if I could find anything that may explain what I had seen the night before(I was just a kid so to me this made sense)..I found four or five odd looking "rocks". I still have them to this day and throughout my life I have asked many people to look at them and tell me what kind of rocks they are but no one can! They are white, smooth like glass and when I took an axe to one I just scratched it (it wouldn't even chip or crack) and it looked like some sort of metal but when we ran a metal detector over it, it did not pick it up. Like I said I know some people will probably have an explanation for this experience, but for me it is something I will never forget.