As a Mufon member and daily skywatcher (not to mention private pilot and fervent aircraft buff), I know most exiting aircraft. I use my 20x50 binocs when watching aircraft to identify the type (mainly 747 - 777, MD-80 and Airbus, occasional military & corporate jets, some commercial helicopters). On Dec. 5 at 1:30 PM EST, on a clear day full of blue sky and NO clouds, while watching a 767 (I believe), I caught a dark grey or black diamond shaped aircraft (?), moving in the opposite direction. Most commercial jets are flying in the 33,000 foot or so range, and this craft looked to be the same size as the jet, but at a higher altitude (Although this could simply be a misperception). What I noticed was the following:1. All commercial jets were leaving pure white contrails (chemtrails??) that day, yet the object in question had NO contrail whatsoever2. The object, which was diamond/hexagonal shape looked like a dark grey (or black) surface, with a silver/ lite grey (possibly white) border on the edge of the diamond, all around the object, covering about 10-20% of the surface area. 3. I noticed either a thermal distortion, similar to heat haze from jet engine exhaust, yet it could also have been the kind of inferior mirage seen of electrostatic discharges from artificial gravity drives. 4. From my knowledge of Air Force black programs, this could have been the Aurora, because after observing this craft for roughly 2-3 minutes while it travelled at conventional velocity (500 mph or so), as I was watching it intently with my binoculars, it instantly disappeared - either an "instantaneous" acceleration, or a "jump" of some kind (an anti gravity 'warp', or the like).I searched the skies for another minute or two, but knew it had left the area. If I were a betting man, I would say it was either the Aurora (or "Licorice Drop") - the commercial traffic would have seen it on his radar.