Due to high importance of the crude oil to the modern society as a source of energy and as raw material for a wide chemical and petro chemical industries. In this study we made assessment of metals and heavy metals  in some Yemeni crude, and fuel oils namely Mareb crude oil blend, Masila crude oil blend plus two samples from Sounah and Hijah oil fields in Masila basin. Fifteen  metals and heavy metals were determined in above samples, but the most indicated were ( Na, K, Mg, ) and ( V, Co, Ni ) using ICP technique and atomic absorption spectroscopy . The order of concentration of metals in Yemeni crude oils were as shown in figures: Na < K < Co < Mg < V < Ni < Ca< Fe < Cd < Al< Zn < Cr < Cu < Pb < Mn. In Fuel oil: Na < Co < V < Mg < K < Ni < Ca < Fe < Al < Cd < Zn < Cr< Pb < Mn < Cu. Comparing concentrations of metals in studied sample, in general were less than in crude oil and fuel oil in many countries. That mean Yemeni crude and fuel oil are the best in quality. The order of concentration of metals in Yemeni crude oils were as shown in figures: Na < K < Co < Mg < V < Ni < Ca< Fe < Cd < Al< Zn < Cr < Cu < Pb < Mn. In Fuel oil: Na < Co < V < Mg < K < Ni < Ca < Fe < Al < Cd < Zn < Cr< Pb < Mn < Cu. Comparing concentrations of metals in studied sample, in general were less than in crude oil and fuel oil in many countries. That mean Yemeni crude and fuel oil are the best in quality.

Due to the high significance of crude oil to modern society as a source of energy and as raw material for a wide chemical and petrochemical industries; in this study, we evaluate the characteristics of certain Yemeni crude, and fuel oils specifically Mareb crude oil blend, Masila crude oil blend plus two samples from Sounah and Hijah oil fields in Masila basin. The general specifications of these crudes and fuel oils are determined and compared with some other regional and international types including Brent and West Texas benchmark crudes using the published data in the specialized literature. It is revealed that Mareb crude oil blend is the lightest and sweetest crude oil followed by Sounah crude while Masila is considered Medium crude and Hijah field is the heaviest with medium sulfur content. Mareb, Masila blends, and Sounah field fuel oils are considered low sulfur fuel oils with sulfur content below the 1% standard marketable fuels; while the Hijah fuel oil slightly above, and this is absorbed within the marketable blend.