Small silver pyramid object just above the power lines observed for about fifteen minutes in the mid 80's

I had this siting years ago and have told many friends about it but have never made a formal report but am doing so now per the Coast2Coast request tonight.  I was about twelve or thirteen years old and my younger brother and I were washing and waxing the car and boat, which we did every summer before going to the lake to water ski.  After finishing I went inside the house then my brother came in excitedly telling me there was a UFO outside and I thought to myself, "Yeah, right!" thinking he was messing with me.  I reluctantly went out and looked up into the sky where he was pointing and saw a perfectly shaped silver pyramid floating about ten or fifteen feet above the power line next to our driveway (only forty or so feet from where we were standing).  The pyramid was about five or six feet tall, had four sides, three of which were dull silver and the fourth which reflected the sun in our eyes every time that side of the object turned our way.  The object was heading East at a leisurly pace and we could walk to keep up with it.  After becoming fairly confident it wasn't going to jet off I ran inside to tell my parents and ask them to get the camera (we had a fairly strict family and I wasn't allowed to touch my dad's camera) but my mom thought I was joking so I ran back outside to watch the object slowly move across the sky.  About fifteen or so minutes into observation the object simply vanished.  Over the years I've tried to find out if others have seen the same thing but have found only a few marginally similar reports.  Needless to say since becoming an adult I always travel w/ a 35mm (now a Nikon D100) because I don't want to miss the opportunity to capture something like this on film.
Date is approximate.  PD