It appeared to be the shape of upside down teardrop.

In early spring of 1986, possibly 1987, 3 or 4 of us saw what appeared to be the shape of upside down teardrop (round part on top).  It kind of looked like a white ice cream cone.  The bottom (pointy part) of the object was pure white and looked like cotton balls stuck together.  No other clouds in the sky except for a few high altitude clouds.  You could barely see the top (round part of the teardrop), but it reflected the sunlight and you could tell it was silver/gray.  This was in the middle of the day at Zerger Elementary.  It was motionless with no sound.  It sat in one spot for about 30-45 minutes then we had to return to class from recess.
One of the kids (we were in 5th grade) begged the teacher to go back out and see this unknown object but the teacher refused.  I wanted to ditch and go home to get a camera (film days).  We were young and it’s been 30 years (2016) but it definitely was there.
More on exact location: Zerger Elementary is in Westminster on the edge of Arvada on about 90th and field street and the object was right above Jeffco Airport now known as Rocky Mountain Metropolitan Airport or possibly above west Broomfield.
From Zerger Elementary looking up and north slightly east, about 40 degrees from the horizon, it was about the size of a nickel at arm's length.  The object was pretty large for a busy area.
I wondered, at the time, how this airport doesn’t see the stationary object of this size?