Among the Relative Index entries for prices are:
Prices—mineral industries 338.23
The comprehensive economics number (also the interdisciplinary number) for prices is 338.52 Prices. The class-elsewhere note under 338.5 General production economics, “Class production economics of specific kinds of industries in 338.1-338.4,” has hierarchical force; consequently, the price of crude oil is classed in the appropriate subdivision of 338.1-338.4 Specific kinds of industries, specifically under 338.2 Extraction of minerals. The scatter note under 338.52 Prices, “For a specific aspect of prices not provided for here, see the aspect, e.g., effects of prices on the whole economy 339.42,” also indicates that oil prices will not be classed in 338.52 Prices.
Among the Relative Index entries for oil are:
Oil (Petroleum) 553.282
Oil (Petroleum)—economic geology 553.282
Oil (Petroleum)—extractive economics 338.27282
At 338.27 Products is the add note that explains how to build 338.27282 Extractive economics of oil (338.27 Products plus 282 from 553.282 Oil). There are also two class-elsewhere notes that should be considered: “Class supply in storage, shortages, surpluses, demand, and projections of these in 333.8; class specific elements of production applied to specific products in 338.23-338.26.” The first class-elsewhere note would be relevant for a work about the effect of oil prices on supply in storage, shortages, surpluses, and demand; by the rule of application, works about the influence of the price of crude oil on something else are classed with the thing influenced. The first note is not, however, relevant for comprehensive works on oil prices. The second class-elsewhere note leads to 338.23 Financial aspects of extraction of minerals, which has the note, “Class here . . . prices.”
Comprehensive works on prices of crude oil are classed in 338.23282 Financial aspects of extraction of oil (built with 338.23 Financial aspects of extraction of minerals plus 282 from 553.282 Oil, following instructions at 338.23), e.g., Oil Markets and Prices: The Brent Market and the Formation of World Oil Prices.