EZ Lube is biodegradable, nontoxic, and environmentally safe. It comes in caulk tubes and is dispensed at a rate of 2 oz. every 300 feet or 4 hours of continuous drilling with a 6" hammer.
Even though you use proper lubricating techniques with rock drill oil, it may be a good idea to keep a couple of tubes on your rig in case your oiler fails or you run out of oil. It can also be used to supplement the rock drill oil by adding a couple of squirts after adding a couple of rods, as it does not adversely affect other lubricants.