black smoke contrails over Bethel, Alaska

Observed black contrail across Bethel, Alaska.  Headed westerly direction.  Contrail was at about a 40 degree angle from ground to event horizon.  
Unusual as it was jet black and contrail was zigzag shaped at top as if wind was blowing it in various directions it was then a soild line and then forked into two distinct contrails and tgen formed back into one. 
Object continued westerly for over ten minutes observation.  Used 7x35 binoculars to watch it.  Minimal clouds at time.  
Round? Object, about dime sized in binoculers and it continued across sky till unable to observe it with glasses.  Black smoke dissipated but object was still visable.