There are several price benchmarks for oil in the world, the main ones are:
Brent oil (from the North Sea)
West Texas Intermediate (from USA)
OPEC Reference Bastket (from the OPEC countries)
Dubai Crude (from the Persian Gulf)
All of them were quoted in USD.
The whole world oil market has been priced in that currency for over 40 years…a kind of monopoly over a key product, not only in the energy market, but in the food market, materials, textile, cargo …
Without notice, after half a century something has changed: China made a big announcement a month ago, an announcement that has got not coverage in the standard media.
China said «Our banking system is ready, all of our communication systems are ready, all of the transfer systems are ready, and from now onwards, any nation in the world that wishes to buy, sell, or trade crude oil, can do it, using the Chinese currency (yuan), not the American dollar.«
How can a country without huge reserves of oil make such a statement?
During the last years, China has sealed agreements with several countries to ensure their oil supply, not only for their internal consumption but to be able to control a market, the oil trading market, that will be the key of survival during the future years, the years where oil will be a scarce good with rising prices, rising demand and decreasing offer.
There is a new empire rising as the old one falls apart.
Sylvia García 
Un comentario en “Oil & US Dollards or Oil & Yuan”