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Diamonds: they're shiny, tough, and an icon of marriage proposals.
钻石闪亮 坚硬 是求婚的标志
On a chemical level, a diamond is just a bunch of carbon atoms bonded together in tetrahedrons.
从化学角度来看 钻石是一堆碳原子紧密结合成的四面体结构晶体
This crystal structure is why diamond is the hardest natural mineral, and beats most man-made ones too!
正是这种晶体结构使钻石成为最坚硬的天然矿物 并且其硬度大于大多数人造矿物
So, we know that diamonds are special, but where do they come from in the first place?
所以我们知道钻石是很特别的 但是它们首先是在哪儿出现的呢？
Diamonds are formed in really extreme conditions,
钻石形成的条件极为特殊
which is why you might find them at the sites of asteroid impacts, and even on meteorites in space.
所以人们可能在行星撞击的地方 甚至是太空中的陨星中发现它们
But we think most natural diamonds were made millions, if not billions of years ago,
但大多数天然钻石 不是在数十亿年前 就是在数百万年
in the splooshy molten rock deep within the Earth.
在地壳深处的熔岩中形成的
Over 160 kilometers beneath the Earth's surface,
在距离地表160多千米深处
the intense heat and pressure forced carbon atoms into that tetrahedral structure to form diamonds.
高温高压 使碳原子们形成为四面体结构 再进一步形成钻石
Then, deep volcanic eruptions blasted them up to the surface, at around 40 kilometers per hour.
然后地底火山岩喷发以大约40千米每小时的速度 把钻石带到地表
If the diamonds came up much slower than that,
如果钻石上升速度比上述速度慢得多的话
the gradually-decreasing pressure would let the carbon atoms shift back into other stable forms like graphite.
逐渐减小的压力 会将碳原子转化为其他稳定的形式 如石墨
At the surface, everything cooled really quickly to make these igneous rock formations called kimberlites,
在地表 岩浆迅速冷却并形成名为金伯利岩的火成岩
with diamonds hiding inside. And, eventually, we humans came along to mine them.
钻石就藏匿其中 然后 人们挖掘出这些矿石
So we know that diamonds are made of squished and superheated carbon atoms,
现在我们知道了钻石是由碳原子经历高温高压后形成的
but we're not exactly sure where that carbon came from. Geologists have two main guesses:
但我们并不确定这些碳原子从何而来 地质学家们主要有两大猜想
For one, there could be some kind of carbon-containing sediment deep within the Earth's mantle,
一是 地幔深处有某些从未面世的
that never saw the light of day.
含碳沉积物
Or maybe the carbon in diamonds came from organic stuff in subducting tectonic plates,
二是这些碳来源于地壳俯冲板块中的有机物
like stuff on the ocean floors, but not coal.
像洋底中的某些东西 但不是煤
That whole "all diamonds are just coal under pressure" thing is mostly just … wrong.
那句话“所有钻石是煤在压力下形成的”多半是无稽之谈
See, coal is a form of organic carbon, but it was made mostly out of ancient plants,
煤是一种有机碳 但煤大多由古代的植物
in layers of sedimentary rock closer to the Earth's surface.
在更接近地表的沉积岩层中形成的
So it formed way later and way higher up than we think most diamonds did.
所以煤的形成大大高于以及晚于多数钻石的形成
These days, scientists can also make synthetic diamonds in a lab with a process called chemical vapor deposition.
目前科学家可以在实验室内用一种叫化学气相沉积的方法 合成人造钻石
Basically, they start with a tiny seed of natural diamond to provide a "pattern."
首先一颗微小的天然钻石作为基底
Then, they use high pressure and temperature tools to turn carbon atoms,
然后他们通过高温高压使
usually from a carbon-containing gas, into layers of diamond.
来源于含碳气体中的碳原子在基底上沉积为钻石
These lab-made diamonds are generally flawless, unlike many natural ones.
这种人造钻石通常很完美 不像天然钻石那样有瑕疵
Plus, they can be cheaper to buy, and have less of an environmental impact than mining natural diamonds.
另外 人造钻石更便宜 与开采天然钻石相比 对环境影响更小
So whether a diamond came from deep within the Earth or a materials science lab,
所以无论是来自地壳深处还是实验室的钻石
it's still the same mineral, just with a different story.
都是一样的矿物质 只是经历有所不同而已
Thanks for asking, and thanks especially to all of our patrons on Patreon who keep these answers coming.
感谢那些提问的人 尤其感谢那些在Patreon上 给予答案的赞助者
If you'd like to submit questions to be answered, or get some videos a few days early, go to patreon.com/scishow.
如果有任何的疑问 或想提前得到一些视频 可以去patreon.com/scishow上留言
And don't forget to go to youtube.com/scishow and subscribe!
别忘了去youtube.com/scishow 订阅我们哦
