Under UV light, clean sand appears purple or black. Some minerals, such as calcium carbonate in seashells, glow blue, as does a shovel handle in the picture above.

紫外线照射下，干净的沙子呈紫色或黑色。有些矿物，如海贝中的碳酸钙，会闪着蓝光，就如同上图中的铁锹的把手。

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They would leave subtle clues in the isotopic composition of the limestone by shifting the ratios of light to heavy carbon and oxygen atoms in its calcium carbonate.

因为如果是那样的话，阳光将会被转换成大量的碳、氧原子保存到石灰岩中的碳酸钙里，而事实却是，岩层的同位素组成（Isotopic composition）中没有留下任何蛛丝马迹。

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As much the cascades of calcium carbonate as the water change color in accordance with changes of the solar light that illuminates them, and the effect is surprising.

无论是碳酸钙阶梯还是池中的水，它们的颜色都随照射的日光的颜色变化而变化，景象十分惊人。

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