The crude oil spectrum
The global oil market is brimming with a smorgasbord of crudes, from the Canadian tar sands extracted with the help of steam and sand, to the lightest US condensates whose color mirrors a glass of fine white wine.
Each crude stream possesses its own unique characteristics, and when refined yields varying proportions of different refined products. Understanding crude quality has never been more important, following the dramatic rise in US shale output, which has transformed the composition of the global oil market.
To reflect this change, S&P Global Platts created a periodic table of oil cataloguing 120 of the most important grades on international markets. Like the periodic table of elements, the list starts with the lightest crudes and ends with the heaviest. The grades are classified by their specific gravity, or density, and sulfur content.
Light crude oils have an American Petroleum Institute gravity of 34 degrees or more, medium crudes have a gravity between API 25-34 degrees, and heavy grades are API 25 degrees or lower. Oil grades with sulfur content lower than 0.6% are considered sweet, while those with sulfur content above this level are classed as sour.
Download the article as a PDF to see a selection of grades that have recently come to the fore, in a turbulent year for the petroleum supply chain.