  Energy supply is mandatory for the production of economic value.
Nevertheless, tradition dictates that an enigmatic 'invisible hand' governs
economic valuation. Physical scientists have long proposed alternative but
testable energy cost theories of economic valuation, and have shown the gross
correlation between energy consumption and economic output at the national
level through input-output energy analysis. However, due to the difficulty of
precise energy analysis and highly complicated real markets, no decisive
evidence directly linking energy costs to the selling prices of individual
commodities has yet been found. Over the past century, the US metal market has
accumulated a huge body of price data, which for the first time ever provides
us the opportunity to quantitatively examine the direct energy-value
correlation. Here, by analyzing the market price data of 65 purified chemical
elements (mainly metals) relative to the total energy consumption for refining
them from naturally occurring geochemical conditions, we found a clear
correlation between the energy cost and their market prices. The underlying
physics we proposed has compatibility with conventional economic concepts such
as the ratio between supply and demand or scarcity's role in economic
valuation. It demonstrates how energy cost serves as the 'invisible hand'
governing economic valuation. Thorough understanding of this energy connection
between the human economic and the Earth's biogeochemical metabolism is
essential for improving the overall energy efficiency and furthermore the
sustainability of the human society.
