74 DISCOVERMAGAZINE.COM
made-up marketing ploy. On the topic of making
things up, the first recorded attempt at synthesizing
diamonds was back in 1880, when Scottish chemist
J.B. Hannay heated sealed wrought-iron tubes
that had been filled with a mix of oils and lithium.
12 Alas, the tubes were prone to exploding. Think
of it as the first diamond boom! that was also a bust.
13 In 1955, however, labs at General Electric built
on earlier research to create diamonds from graphite,
another carbon allotrope, that had been subjected
to extremes of pressure (nearly 1 million pounds
per square inch) and temperature (3,100 degrees
Fahrenheit). 14 In subsequent decades, GE and
other labs around the world developed additional
techniques for creating synthetic diamonds, most of
which have industrial applications such as drilling
or grinding, for which the material is extremely
well-suited. 15 Speaking of suits, playing cards were
likely invented in China more than a millennia ago,
but diamonds weren’t one of the four suits in a deck
until relatively late in the game. 16 The cards appear
to have spread along trade routes, first to Egypt
and then to Europe by the 14th century. European
merchants initially kept the suits created by the
Egyptians — swords, wands, cups and coins. 17 By
the late 1400s, French enthusiasts had developed the
suits that we know today: clubs, spades, hearts and
diamonds, the latter representing the merchant class
and wealth acquisition. 18 In Renaissance folklore,
however, the diamond was considered an amulet that
warded off demons and madness. 19 What Renais-
sance folks called madness, we now understand
as pathology. A 2017 British Journal of Psychiatry
study urged health care practitioners to assess
mental illness not just with formal measures but also
through simple observation. 20 The study’s authors
were inspired by an unlikely source: a documentary
about Syd Barrett, founding member of iconic band
Pink Floyd. Barrett left after a mental breakdown,
poignantly chronicled in the group’s tribute song to
him, “Shine On, You Crazy Diamond.”^ DDiscover senior editor Gemma Tarlach remembers when
you were young and shone like the sun.1 Diamond, a particular form, or allotrope, of
carbon, is the hardest material we know of. It’s more
than twice as hard as the closest competition, silicon
nitride and cubic boron nitride. 2 That extraordinary
hardness arises from a strong and inflexible structure:
Five atoms form a tetrahedron and share electron
pairs with each other. 3 In nature, diamond is
typically created under extremes of pressure and tem-
perature, deep in Earth’s mantle — about 90 miles or
more beneath our planet’s surface. 4 Except for space
diamonds, of course. In 2017, researchers re-created,
for the first time, the conditions under which they
believe diamond rain forms in Uranus and Neptune.
5 These planets have internal temperatures just right
for diamond formation. As hydrocarbon gases sink
toward their cores, increasing pressure squeezes out
the hydrogen atoms and presses the remaining car-
bon into diamond, which travels through the planet’s
heart as very pricey precipitation. Researchers believe
a different process creates atmospheric diamond rain
on Saturn and Jupiter. 6 Farther afield, the exoplanet
55 Cancri e was once thought to be made mostly
of diamond. The 2012 findings were based on data
that suggested the planet had abundant carbon
under conditions favorable for the mineral’s
formation. 7 Sadly, 55 Cancri e lost some of
its luster the following year when another
team’s analysis revealed there wasn’t quite
so much carbon on the planet — making
it much less likely to be a diamond in the
rough. 8 Back on Earth, diamonds destined
for jewelry are, of course, rated by carat, cut,
clarity and color, but the latter is a bit of a misnomer.
Diamond is naturally transparent. Any hint of hue
indicates an impurity or structural deformation.
9 For example, a few nitrogen atoms among a dia-
mond’s millions of carbon atoms can make the rock
appear yellow or brown, while blue diamonds have
been besmirched with a few boron atoms. 10 The
Hope Diamond, the most famous blue diamond, is a
lot smaller than it once was. When it was first mined
in India in the mid-17th century, the now 45.52-carat
rock may have weighed more than 112 carats. 11 As
for the Hope Diamond’s “curse”? Sorry, it was aDISCOVER (ISSN 0274-7529, USPS# 555-190) is published monthly, except for combined issues in January/February and July/August. Vol. 39, no. 3. Published by Kalmbach Publishing Co., 21027 Crossroads Circle, P.O. Box
1612, Waukesha, WI 53187-1612. Periodical postage paid at Waukesha, WI, and at additional mailing offices. POSTMASTER: Send address changes to DISCOVER, P.O. Box 62320, Tampa, FL 33662-2320. Canada Publication
Agreement # 40010760. Back issues available. All rights reserved. Nothing herein contained may be reproduced without written permission of Kalmbach Publishing Co., 21027 Crossroads Circle, P.O. Box 1612, Waukesha, WI
53187-1612. Printed in the U.S.A. FROM TOP: BILLION PHOTOS/SHUTTERSTOCK (2); JOHN R. FOSTER/SCIENCE SOURCE; BUNDIT JONWISES/SHUTTERSTOCK; SCIENCE SOURCEDiamonds BY GEMMA TARLACH
20 Things You Didn’t Know About ...
From top: Only a
small fraction of
diamonds are cut for
jewelry; fewer still
attain the status of
the Hope Diamond.
Despite symbolizing
wealth, even in a
deck of cards, most
diamonds end up in
an industrial setting,
like this diamond-
tipped drill.