Most commonly used parameter(s) for hydrocarbon include the API Gravity and Sulphur content. Crude normally divided into two type which is SWEET crude and SOUR crude that reflects the percentage of sulphur in the crude oil.
Generally used, sweet crude have less than 1% of sulphur BUT sour crude have more than 1% sulphur. According to Dictionary of Petroleum Exploration, Drilling and Production by Norman J. Hyne , low-sulphur crude has less than 0.6% sulphur by weight, intermediate-sulphur crude has 0.6% - 1.7%, and high-sulphur crude has more than 1.7%.
Higher sulphur crude oil are more corrosive, thus these sulphur contents need to be remove or reduced into certain level that permitted before going to the consumer. This make low-sulphur crude oil very high in demand in the sulphur content perspective.
Early prospectors would taste and smell the crude oil for quality check , sweet crude oil has pleasant smell and soft sweet taste and vice versa.
According to the ExxonMobil crude oil information , these are the top 5 of their crude oil production; Terengganu, East Peninsular Malaysia (0.00%) have the least content of sulphur followed by Ormen Lange, Norwegian Sea (0.00%), Sable Island, Canada (0.002%), Woollybutt, Australia (0.01%) and Tapis, East Peninsular Malaysia (0.04%).