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EARLIEST GOLD COIN
CHANGES HANDS
An extremely rare version of the
first gold coin ever struck in human his-
tory was purchased from Austin Rare
Coins and Bullion, Texas, by an Austin
collector for a six-figure sum. The ob-
verse, or “heads” side of the coin, de-
picts a lion and bull confronting each
other. Instead of a reverse design, the
“tails” side shows two overlapping
squares, the double-incuse mark left
by the punch that was struck to force
the gold into the obverse die. Issued
by King Croesus in Lydia (now Tur-
key), the coin dates to approximately
560 B.C. and is preserved in near-mint
condition. While the earliest coins were
made from electrum, a naturally occur-
ring alloy of gold and silver, Croesus
abandoned the alloy in favor of pure
gold and pure silver. Soon afterward,
nearly every mint in the Greek and Per-
sian world began issuing pure metal
coins.
austincoins.com.
MICRO AIR VEHICLE WINGS
SHAPE SHIFT ON THE FLY
Researchers from the Universi-
ty of Southampton, UK, and Imperial
College London designed bat-inspired
Are you working with or have you
discovered a material or its properties
that exhibit OMG - Outrageous
Materials Goodness?
Send your submissions to
Julie Lucko at
julie.lucko@asminternational.org.
OMG!
OUTRAGEOUS MATERIALS GOODNESS
First gold coin ever struck. Courtesy
of PRNewsFoto/Austin Rare Coins
and Bullion.
Model car with carbon fiber roof and bat-
tery electrodes made of wood. Courtesy
of KTH.
membrane wings that can adapt in-
flight to the forces they experience. The
wings have no mechanical parts, but
instead function like artificial muscles,
incorporating electroactive polymers
that allow them to stiffen and relax in
response to an applied voltage. The
development paves the way for a new
class of unmanned micro air vehicles
(MAVs) with improved aerodynamic
properties, longer flight ranges, and
an economic advantage over current
models. “This is a paradigm shift in the
approach to MAV design,” notes Dr. Ra-
fael Palacios of Imperial’s department
of aeronautics. “Instead of a tradition-
al approach of scaling down existing
aircraft design methods, we constant-
ly change the membrane shape under
varying wind conditions to optimize
aerodynamic performance.” Some-
times as small as 15 cm across, MAVs
are increasingly used in a wide variety
of civil and military applications, such
as surveying remote and dangerous
areas.
www.southampton.ac.uk,
www. imperial.ac.uk.
WOOD-BASED CAR BATTERY
LIGHTENS THE LOAD
The world’s first model car with a
roof and battery made of a wood-based
carbon fiber composite was produced
jointly by Swedish researchers from the
KTH Royal Institute of Technology and
research groups Innventia and Swerea.
Although built on a toy scale, the pro-
totype vehicle represents a significant
step toward reducing vehicle weight
using renewable materials. The key in-
gredient in the carbon fiber composite
is lignin, a constituent of plant cell walls
and the second most abundant natural
polymer in the world, surpassed only
by cellulose. Lignin batteries can be
produced from renewable raw mate-
rials, in this case the byproduct from
paper pulp production. “The lightness
of the material is especially important
for electric cars because then batteries
last longer,” explains Göran Lindber-
gh, professor of chemical engineering
at KTH. “Lignin-based carbon fiber is
cheaper than ordinary carbon fiber.
Otherwise batteries made with lignin
are indistinguishable from ordinary
batteries.” Lindbergh says carbon fi-
ber bodywork and batteries eventually
could be combined to simultaneously
manage mechanical loads and store
electrical energy.
www.kth.se.
Southampton-Imperial MAV. Courtesy of
University of Southampton.