If you're living in Mesopotamia in 3000 BCE, how do you buy things?
There are no cards, no ATMs no cash of any kind… bartering was a valuable part of any
exchange, until the invention of international trade, and then money.
Money has been made of grains, shells, livestock, beads, and finally precious metals.
The problem is, when we translate the value of something inherently valuable -- like a
cow, or a sack of grain -- to something with no value, like a metal or a piece of paper,
people will try to fraudulently jump on the value bandwagon; we call this counterfeiting
-- and it was so prevalent in Civil War-era America, the Secret Service was created to
combat it at the time, one-third of all US currency was likely fake.
Today, it's FAR less.
Currency is in a constant state of cold war with counterfeiters, so science was recruited
to help stem the fraud.
In 1739, Benjamin Franklin's printing firm created nature prints on colonial bank notes
to distinguish them from fakes.
Impressions were made on the notes using actual leaves and the process was so innovative it
wasn't fully understood until centuries later!
Today, our money has dozens of little security additions to verify the bills are real.
Firstly, the money isn't regular paper!
If someone handed you a perfect reproduction on printer paper, you'd KNOW instantly it
was fake.
The "paper" we use for money is 75 percent discarded chunks of blue jeans and 25 percent
linen; it's called rag paper and it's how you can wash our money and it comes out just
fine.
The Euro is made with 100 percent cotton.
Some other countries don't use paper at all, like Australia who have used polymer money
since 1988.
That pen you sometimes see at the store that they use to mark the bill with?
That's an iodine pen.
The iodine reacts with tree cellulose differently causing a chemical reaction and color change;
instantly revealing the fakes.
Outside of the paper, the inks are steeped in tech.
For example, some Euro notes have europium ink.
Europium is highly phosphorescent, so, under blacklight the europium ions absorb UV light
and re-release it in the area of ​​the red, green or blue depending on the chemistry
used -- which is a secret.
U.S. notes, have phosphorescent ink too which is how vending machines spot fakes -- plus,
photocopiers won't print them because of a special reflective ink which allegedly triggers
a halt in the machine.
On top of that some of the lines on American money are actually tiny words, there's a watermark
which can't be scrubbed off, a strip inside the note, AND little red and blue hairs embedded
in the paper.
All these are classic money tech, but unfortunately not everyone looks close enough at their money
to really scan these features…
Unfortunately for counterfeiters, a study in ACS Nano from last year caught the eye
of someone at the Treasury Department.
The study explored a longhorn beetle that can shift from gold to red as the humidity
changes.
Inspired by the tiny scales on this beetle, the researchers designed a bleach-resistant
photonic crystal ink that can change from green to yellow or red when exposed to ethanol
vapor.
Breathe on it, and mesoporous silica nanoparticles in the ink absorb minute amounts of humidity,
thickening them, and refracting different colors.
Imagine if the green trees around the Lincoln Memorial could turn the reds and yellows of
autumn.
Even with all the tech counterfeiting is still going on.
60 percent of the 88.7 million dollars seized in 2013 by the Secret Service was printed
using at-home inkjet or laser printers.
In fact, the first "affordable" laser printer debuted in 1992, and in 1996, the U.S. Treasury
committed to the first major redesign of paper money in almost 70 years.
Coincidence?
I think not!
Today, money is redesigned about every seven years… except the poor Washington… he's
not been updated since '63[10].
It's about time.
At least we're getting a woman on our money, finally!
The thing is, the United States isn't always fighting Alice and her inkjet, sometimes countries
like North Korea create superbills that can trick even the best detectors!
For more on counterfeiting around the world, check out TestTube News here.