It is petroleum based, as I understand, relatively thick, and insoluable. Makes a good protectant for steel. It was used in the oil bottles issued to British troops for lubrication and protection of their Martini Henrys and Sniders. I am not sure what effect BP has on this oil as some petroleum products react negatively to BP and some don't. Been in use for over 150 years I understand.
Rangoon oil is actually a heavy petroleum distillate roughly along the lines of kerosene and fuel oil. It has a slow evaporation rate and was used as a rust preventative by the British around the 1850s. They found that it worked rather well, especially in hot and steaming jungles. The name comes from the fact that the first source was from a natural oil well found in Rangoon (now Yangoon), Burma (now Myanmar).
