Stever,
Found what I think you are looking for on page 3-5 of the Welding Inspection Technology book. It gives a chart with the significance of the last digit of SMAW Identification.
E6010 = DCEP, Arc Digging, Penetration Deep, Covering/Slag Cellulose-sodium, iron powder 0-10%.
E7018 = AC or DCEP, Arc Medium, Penetration Medium, Covering/Slag Low hydrogen-iron powder, iron powder 25-40%.
John Wright