Of course, these would make for pretty big pebbles:
These bright pots of color—at an oil depot in Tokyo—have a far more important function for the Japanese. As Anthony Qugley explains in his caption:
Japan lacks significant domestic reserves of fossil fuel, except coal, and must import substantial amounts of crude oil, natural gas, and other energy resources, including uranium. Japan relied on oil imports to meet about 42 percent of its energy needs in 2010. Japan was also the first coal importer in 2010, with 187 Mt (about 20% of total world coal import), and the first natural gas importer with 99 bcm (12.1% of world total gas import).
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