TRIANGLE flies over I 10 IN AZ.

I was driving my big truck on my way to L.A.from Phoenix Az. headed west on 10 not too far east of Quartzsite Az.when i looked to the north to see this triangular shaped huge craft with 3 lights-one at each point.  I watched it go across 10 headed south,when it got to the mountains just to the south of I 10 it shined what looked like a headlight because it lite up the whole mountains,this craft appeared to be about 1200 ft in the air. It was not very far above the mountains when it went over them. I did get on the CB and ask other drivers if they saw what i saw and about 10 guys responded and said they did see the same thing.   
So if im the only report of this event i will be very suprised but i just wanted to finally report it!!!
Witness indicates that the date of the sighting is approximate.  PD