Hi All;
I noticed I have a slight oil leak, I believe from the oil pan, in my '87 Westy with a Golf Gen. V engine.  At a previous time, I had to drain the oil, from inadvertently overfilling the pan and put the oil in mixed containers while on the road.  At the time I didn't have anything to mark them with.  Now while topping off,  I think I may have mixed oil jugs and put dino oil in with the synthetic, which I normally use.  Here's my 2 questions.  1) can one tell the difference, from visual inspection and feel, between synthetic and dino oil?  And 2)  is it OK to mix the two until the next oil change?

Dave B.