When these rocks break down into the grains that make up the sand on our beaches, their colour is mostly determined by the presence or absence of iron.

当岩石分解成为颗粒够成沙滩时，颜色则是由铁元素氧化物的存在与否决定的。

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This year he completed what is believed to be the first ever fracture stimulation procedure in Turkey: injecting a mixture of water and sand at high pressure down the wells to break up rock and release gas.

FORBES: Magazine Article