Saucer shape , noiseless, changed color from greyish black to black and seemed to emit black light. to camouflage itself in darkness.We saw it in the darkness of the town. It was saucer shape with the center of it like a dome on top of the aircraft. The disk area did not appear to be very thick yet much, much bigger than the dome area. It was big, about 2/3 the length of a 747 but round. It was pretty low, about the height of a five story building. I would not necessarily use the word 'metallic' to describe the material of its exterior, neither was it plastic: it was something else, like maybe a combination of materials. It did not make any noise nor was it showing any lights. Neither was it blowing any air out very strongly as it was near some very tall trees and the branches were not moving. It seemed powerful, it hovered there with precision. We could all see it from the balcony; we were a block away from it. Then, as if they/it realized that we could see it, the grayish black color of its exterior which made it visible in the darkness in a matter of seconds began to turn black and well it was as if it was emitting black light around itself to camouflage itself at the same time it started to move up slowly. Then it completely disappeared. We went outside where it had been and we tried to see if we could still see it in spite of its camouflage by perhaps seeing that it was covering a part of the sky. But, no, it had completely disappeared from sight. That was some impressive technology. Why Moca? There is absolutely nothing of interest happening there. Perhaps worth mentioning, however, is that the previous year for the first time in the history of the region an international airport was inaugurated at the town's border with Santiago. The craft sited however does not appear to need an airport to take off and land. It could just go up and down. The other possible thing that could be of interest is that a 6.7 earthquake had just occurred - a couple of weeks prior to the sighting. I saw what I saw. I did see an unidentified flying object. I hope this information helps someone, someday.((NUFORC Note: Source of report indicates that the date of the sighting is approximate. PD))