> Named davemaoite after prominent geophysicist Ho-kwang (Dave) Mao, the mineral is the first example of a high-pressure calcium silicate perovskite (CaSiO3) found on Earth.
A few micrometers in size. I dont think in micrometers, so I must convert to a more familiar unit. A few .001mm in size. That's tiny. An average piece of paper is .1mm thick. This is around the size of the thickness of ink on the paper.
You joke, but this would (perhaps even more absurdly, really) be called a "tenth" by most people who care about imperial units at this scale (as explained in a sibling comment)
This is pretty anti-intellectual isn't it? People, in my opinion rightly, make fun of measures expressed in libraries of congress or Olympic pools or African elephants, and then an article actually uses a normal SI measure and that gets disparaged too? What are authors supposed to do?
There was nothing disparaging about the comment. There is also nothing anti-intellectual about comparing things you don't know to things you do, in order to contextualize information. And he did that by first converting to mm, so did not abandon SI measurements at all. I agree that when we are talking about more common measurements it can be gratuitous or grandstanding, much like talking about things over 1x size in percent, as e.g. 450% bigger, etc. But that is not the case here.
Yeah, for folks with experience in machining (in the US), this is a "tenth" (a pretty fundamental unit in machining is a thousandth of an inch, or a "thou", for very high precision work, that can be divided into "tenths", or ten thousandths of an inch).
A mil, or a thou, really isn't good enough for high precision work. 25.4 microns is a lot. A surface flat to that isn't really that flat. An instrument that measures to that isn't really a very high precision instrument. Microns are a pretty good unit.
EDIT: There's this rule of thumb (I might be getting this slightly wrong) that one in a million accuracy/precision is about what you can expect to achieve without resulting to exotic means (at least order of magnitude). So microns of flatness over a meter e.g. Trying that with imperial units just breaks my mind, what's a million mils. Sure I can calculate that. But it's like a pretty useless measure. So accuracy of one thou over a million mils is sort of weird. (1000 inches which I'd have to translate to some normal unit... 25.4 meters ;) ).
I think YZF just mis-parsed your sentence, and thought you meant a thou is for very high precision work, while you meant that a tenth is for very high precision work.
(That said, I'd add -- measuring to one part in 10^6, for anything except time, is challenging but still very doable; machining to one part in 10^6, for anything beyond very simple shapes, does require pretty exotic methods or very great care, and to verify it you have to measure to one part in 10^7).
The most interesting part or me was that the diamond came from 600km below the earth's surface. Maybe this is common knowledge, not for me. It's pretty cool to think that we have access to such things. If we could dig down that far, would there be an abundance of diamonds?
The article says the diamond formed at that depth, but I assume the rock rose to a higher depth before it was extracted. I believe the deepest depth to which we have drilled is on the order of 10 km.
I've alway wondered why they never went deeper. Turns out the answer is in hindsight obvious, but very unsettling:
> The unexpected decrease in density, the greater porosity, and the unexpectedly high temperatures caused the rock to behave somewhat like a plastic, making drilling nearly impossible.
We could use the unexpectedly high temperatures as a heat source for geothermal energy. Make money selling the energy for ten, twenty years,... until the temperatures fall and the rock becomes rigid. Then drill another kilometer, funded from the geophysical exploration budget.
Temperature too high again? Have a long pause to make a little money from geothermal energy.
Geothermal plants can trigger earthquakes [1], so it's probably unwise to build a lot more geothermal plants to meet global energy needs without addressing that risk first, especially near populated areas.
It's always strange to thing of the vast distances we can send things into space compared to our inability to travel extremely short distances beneath our feet.
> Named davemaoite after prominent geophysicist Ho-kwang (Dave) Mao, the mineral is the first example of a high-pressure calcium silicate perovskite (CaSiO3) found on Earth.
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