Russian geologists believe future diamond deposits may be discovered by the way the soil smells. The rocks in which diamond deposits are buried release gases whose composition is different from non-diamondiferous soil.

The research team studied the Russian plain’s fields of kimberlite (blue earth) in the blow holes that are created when gases burst through the earth’s crust strata. Diamonds have never previously been found there, but the presence of diamonds was discovered in about 10% of the 1,500 blow holes examined.

The technique of analyzing the gases of rocks and soils in the earth’s "breathing" zones may also be used in the search for oil, gas, and precious metals, the researchers conclude.

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