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Carbonados, sometimes referred to as black diamonds, have been on geologists' radar since their discovery in 1841.
黑金刚石，有时也被称为黑钻石，自1814年发现以来一直备受地质学家的关注。
They look neat, and have some cool industrial uses.
它们看似纯净，还有一些很酷的工业用途。
But there's a lot we don't understand about this particular flavor of sparkly rock.
但是对于这种闪闪发光的石头，我们还有很多不了解的地方。
Like where on Earth they come from. If they come from Earth at all.
比如它们究竟来自何处，或许它们就是来自地球呢？
As you might expect, carbonados are black. Or at least, they're dark.
正如你所料，黑金刚石是黑色的。至少，它们是暗色的。
They're opaque, and really can range anywhere from grey to pink to green. And they're sometimes used in jewelry.
它们是不透明的，可以是灰色、粉色和绿色。并且有时会将它们用于珠宝。
But because carbonados are rarer than diamonds, much of the black diamond jewelry on the market
但因为黑金刚石比钻石更加稀有，所以市面上的很多黑钻石珠宝
is made from naturally occurring diamonds with darker colors, or ones that have been treated to change their color.
都是由天然的深色钻石制成的，或者经过处理后改变了颜色的。
On the other hand, carbonados, though made of diamond, are a little different from the one you might be picturing.
另一方面，尽管黑金刚石是由钻石组成，但它们和你想象的有着细微的差别。
They're crystallized carbon, so they still fall into the diamond family,
它们是结晶碳，所以它们仍然属于钻石家族，
but instead of tight, continuous, uniform crystals like most diamonds,
但和大多数紧密、连续、均匀的晶体钻石不同，
they're aggregates of a bunch of randomly arranged microcrystals.
它们是一堆随机排列的微晶体的聚集体。
This arrangement makes carbonados something geologists refer to as a xenomorph.
这种排列使得黑金刚石成为了地质学家口中的异形。
In part, this means that carbonados are more porous than single-crystal diamonds.
在某种程度上，这意味着黑金刚石比单晶钻石有更多的孔。
But this weird — one might even say Alien — crystal structure also makes carbonados extra useful for industrial purposes.
但这种奇怪的晶体结构（有人甚至可能称之为怪物）也让黑金刚石多了一些工业用于。
Diamonds are really hard, and we like to take advantage of that fact by using them for cutting and drilling.
钻石真的非常坚硬，我们利用这一优势将它们用于切割和钻孔。
But even diamonds can eventually crack or break, and then you have to replace the cutting surface with new diamonds.
但即便是钻石最终也会破裂，然后你必须用新的钻石来代替切割面。
However, carbonados have an advantage. Since they're aggregates, rather than uniform crystals,
但黑金刚石有一个优势。由于它们是聚集而非均匀的晶体，
any break will be confined to that single piece, and not spread throughout.
任何裂口都将局限于那一块，而不会扩散开来。
This makes carbonados as hard as diamonds, but much tougher.
这让黑金刚石和钻石一样甚至更加坚硬。
Hardness is a material's ability to withstand abrasion, and here, carbonados match your typical diamond.
硬度是一种材料耐磨的能力，在此黑金刚石与典型钻石的硬度相当。
Toughness, on the other hand, is how well a material resists shattering when force is applied,
另一方面，韧性是一种材料在受到外力时抵抗粉碎的能力
and that's where carbonados come out on top.
在这一方面黑金刚石胜出。
Thus, they allow cutting and drilling tools to last longer and require less maintenance over time.
因此，它们可以让切割和钻孔工具更耐用，并且随着时间的推移，需要的维护也更少。
But the main reason scientists are interested in carbonados isn't what they look like or even what they can do — it's their origin.
但科学家们对黑金刚石感兴趣的主要原因并不是它们的样子或用途，而是它们的来源。
And the origin is… we don't know.
我们还不知道它们来自何处。
The majority of ordinary diamonds form in the intense heat and pressure of the Earth's mantle,
大多数普通钻石是在地幔的高温高压下形成的，
before eventually being blasted to the surface by volcanoes, and encased in rocks with characteristic mantle minerals.
最终被火山喷发到地表，被包裹在岩石里的特有的地幔矿物中。
But that doesn't seem to be the case with carbonados. They're not found in mantle rocks,
但黑金刚石的情况似乎不一样。它们不是在地幔岩石中被发现的，
and tend to include metals in their structure that wouldn't make sense if they formed in the mantle.
并且它们的结构中还含有金属元素，如果它们是在地幔中形成的，那这就说不通。
Theories for how carbonados form include the heat and pressure of meteorite impacts,
黑金刚石的形成理论包括陨石撞击的热和压力
or possibly even radiation transforming carbon in the mantle.
甚至可能是地幔中辐射转化的碳。
However, neither method produces diamonds large or numerous enough to account for existing carbonados.
但这两种方法都不能产生足够大或多的钻石来解释现有的黑金刚石。
Another contender is subduction zones, boundaries where tectonic plates collide and get shoved down into the mantle.
另一种说法是俯冲带，即构造板块碰撞并被推入地幔的边界。
The pressure and heat of this process would be plenty sufficient, but again,
这一过程的压力和热量相当充足，但是
we should find mantle minerals present alongside carbonados.
我们应该能够在黑金刚石旁边找到地幔矿物。
All this leads scientists to suspect that carbonados must come from interstellar space.
所有这一切都让科学家怀疑黑金刚石一定来自星际空间。
The crystals could form out there in some distant, carbon-rich spot, in the absence of Earth mantle minerals, and then get deposited here via asteroid.
在没有地幔矿物的情况下，这些晶体可能在某个遥远的富含碳的地点形成，然后通过小行星沉积在这里。
Plus, the space option could easily account for those head-scratching metal inclusions.
另外，太空说法可以很容易地解释清楚那些令人挠头的金属夹杂物。
Furthermore, carbonados are only found in Brazil and the Central African Republic,
而且黑金刚石仅在巴西和中非共和国被发现，
which could be explained by an intense barrage of space rocks back when Africa and South America were part of the same supercontinent.
这也可以用—当非洲和南美洲同属同一块超大陆时，太空岩石的密集进攻—来解释。
All of this makes carbonados one of the few geological phenomena where the most likely explanation invokes outer space.
所有这些都让黑金刚石成为了少数最有可能用外层空间来解释的地质现象之一。
Because once you've eliminated the impossible… well, you know. Thanks for watching this episode of SciShow.
因为一旦排除了不可能……嗯嗯，大家懂的。感谢收看本期《科学秀》
We'd like to thank our patrons for making this and every episode possible.
感谢我们的赞助人，有大家才有每一期的节目。
If you'd like to support us, and earn cool perks along the way, check out patreon.com/scishow.
如果想支持我们，并获取超酷特权，前往patreon.com/scishow。
