Iran supplies mainly two grades of Bitumen: Bitumen 60/70 and Bitumen 85/100 which are also known as Bitumen Penetration grades. Both grades are refined Bitumen from Vacuum Bottom raw material extracted from crude oil.
Bitumen grades 40/50 and 80/100 are also available from Iranian refineries, while they may come in smaller quantities since the demand is less. sometimes suppliers consider 80/100 and 85/100 grades same, as the test results are hardly different.
There are other grades which are asked very rarely like 100/120 which is suitable for cold areas or 35/50 which is for good to be used in humid and hot locations.
please visit: Iran Bitumen Grades and Specs