Top Quality: WTI is considered a "mild sweet" crude oil, that's simpler to refine, when Brent is often a mixture of crude oils, which includes equally "mild sweet" and "large sour" grades. Screening is by references that POs check with one another for, not by released assessments or from other https://maps.app.goo.gl/VhAGTRCDGTuVhHJa8