What would happen if we desalinated the entire ocean? 28 (1/2) – Science Mysteries Explained

Q:
A:
earth science
IDIOT’S GUIDES: SCIENCE MYSTERIES EXPLAINED
26
Are gold and diamonds good for anything besides
jewelry?
Humans spend a huge amount of time and money looking for gold and diamonds. We
even fight wars over them. Sure, most people agree these minerals are pretty and desir-
able, but are they actually good for anything more than looking pretty?
We haven’t been wasting our time: it turns out gold and diamonds both have unique properties that make
them useful for all kinds of things, from electronics to medicine and space travel. That said, while gold is
genuinely rare, diamonds can be made cheaply ….
For as long as humans have been able to work met-
als, we’ve been obsessed with gold. This ultra-rare,
soft, shiny metal does something to our brains—we
lust after it, we’ll travel the world looking for it, and
risk our lives to dig it out of the ground.
Gold is very rare on Earth, occurring only 21
times in every billion atoms on the planet. Put it
this way: if humans could be made of gold, there
would be only 147 golden people among our popula-
tion of seven billion.
Diamonds, on the other hand, are made of
carbon. Yes, the same stu as trees and people
and pencils. There are no tricky trace elements
in diamond, but natural diamonds are found
only in areas where the crust has been subject-
ed to tremendous heat and pressure. Diamond
forms when carbon is crushed and squeezed
and its atoms are forced into a particular crystal
lattice that sort of looks like little pyramids.
Diamond is very hard, once considered the
hardest naturally occurring substance—though
scientists have discovered other ultra-rare
forms of carbon that are a little harder. That
makes it very useful in industrial applications,
especially super-fine drills. Diamond dust is
also used for grinding, and tiny specks of dia-
mond can be embedded in disc sanders.
EARTH SCIENCE
27
Because diamonds are only made of carbon, we can
actually make them artificially. These artificial diamonds
have no value as gemstones, because they’re too perfect—
they have no interesting coloring or exceptional charac-
teristics.
We mine about 60,000 pounds of diamonds from the
Earth every year and make another 240,000 pounds.
Eighty percent of natural diamonds are used for indus-
trial purposes, and the remainder are sold as gems. Very
expensive gems. Why so expensive? The simple answer is
because people are prepared to pay for them, so compa-
nies charge what they want. There is no special reason for
diamonds to be the most expensive type of gemstone.
Gold, on the other hand, has many applications beyond
jewelry. Gold is extremely good at reflecting light and heat,
so it’s used for insulation on very sensitive electronics,
such as satellites and space probes. Ever seen a NASA
astronaut with a gold-colored visor on his suit? The visor
is actually coated in gold to reflect sunlight and prevent
overheating.
Gold can be worked in such a way to become entirely
transparent. It’s then layered onto aircraft windows and
hooked up to a heating system. The system pumps heat
through the gold layer—it’s very good at conducting heat—
and prevents the window from icing over.
High-grade electronics also use gold to conduct elec-
tricity. If you buy expensive cables for your home theater,
it’s likely the ends will be coated in gold.
Gold is also useful in medicine, for testing for the pres-
ence of viruses. And of course gold is an excellent replace-
ment for human teeth.
And then there’s money. People still invest in gold and
track its global price.
How much rarer is gold than diamonds? A lot: as of
2013, only 192,000 tons of gold have been mined in the
whole of human history.
Industrial
Diamond Cutting Blade
Gold
Plated Coaxial
Male Pin