WHEN IT COMES TO BUILDING tough, resilient materials without wasting energy, few human manufacturers can compete with Mother Nature. One of her most intriguing achievements is nacre, commonly known as mother-of-pearl, a material that is much stronger than the sum of its parts. “[Nacre] is effectively chalk, but it doesn't break like chalk. When I think of chalk, I think of a very brittle, delicate material," says Robert Hovden, a professor of materials science at the University of Michigan and one of the researchers on a study involving nacre. Last year, his team uncovered new information about the nano-level structure of nacre that could open new frontiers in the world of human-made supermaterials.
The study, published in Proceedings of the National Academy of Sciences, focuses on nacre's structure at the nanoscale level-lengths of a billionth of a meter, even smaller than a wavelength of light. Using an electron microscope, the researchers noticed that inconsistencies in the nacre's brick-and-mortar structure led to "corrections" in future layers. When an asymmetrical nacreous layer corrupted the pearl's symmetry, future layers "adjusted” their thicknesses to make the pearl more spherical.
Clams and other mollusks construct pearls by blanketing a “bead nucleus," or a small object inside the pearl sac, with tiny alternating layers of calcium carbonate and organic protein. These layers make up nacre. “It's sometimes referred to as brick and mortar,” explains Neil H. Landman, curator emeritus at New York City's American Museum of Natural History. "The bricks are the nacreous [calcium carbonate] tablets; the mortar are the organic sheets between the tablets."
Hovden and seven other researchers analyzed the “periodicity of this brick-and-mortar structure, or how uniform the layers of nacre were.
This story is from the March - April 2022 edition of Popular Mechanics.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 8,500+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the March - April 2022 edition of Popular Mechanics.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 8,500+ magazines and newspapers.
Already a subscriber? Sign In
Cutting the Cord
THE HANDHELD CIRCULAR SAW IS PERHAPS THE MOST VERSAtile power tool for cutting wood.
BUILDING COLLAPSES IN U.S. HISTORY
THE CASCADING FAILURES BEHIND ONE OF THE WORST
How Three Amateurs Solved the Zodiac Killer's '340' Cipher
The mysterious code stumped the FBI and NSA for 53 years. What does the key, and the resulting solution, tell us about the infamous murderer?
POPULAR MECHANICS TOP AWARDS 2024
For more than 120 years, Popular Mechanics has been a heavy-duty brand. We see no reason to change that now.
How This Particle Could Break Our Understanding of Reality
EINSTEIN'S SPECIAL THEORY OF relativity teaches us that nothing can accelerate past the speed of light. But what if, when you were born, you were already moving faster than light? What would that look like?
The Right Way to Use a Fire Extinguisher
A FIRE EXTINGUISHER IS MORE THAN A of one 5-gallon bucket becomes the size of 64 burning buckets. Just 180 seconds after it begins, a fire can be transformed from a nuisance to a room-size, life-threatening inferno.
How the World's Largest Spherical Structure Was Built
THE SHINY, NEW LAS VEGAS SPHERE IS more than just a 17,600-seat amphitheaterstyle venue hosting a U2 residency. Since its opening in September 2023, it's become the world's largest spherical structure, at 516 feet wide and 366 feet tall.
The Army's Drone-Killing Laser Weapon
THE U.S. ARMY FIELDED ITS FIRST LASERweapon-equipped unit in October. Based at Fort Sill, Oklahoma, the unit took possession of four laser-equipped Stryker infantry combat vehicles, each mounting a 50-kilowatt-class laser-weapon system. The combination of Stryker and laser can down both artillery, such as mortars and rockets, and drones in-flight.
Why It's So Hard to Mine the World's Largest Lithium Deposit
A Pass, or Peehee Mu'huh to the local Paiute people has been mined since the 1970s, so the new analysis merely confirms what locals have long known about the area.
WHAT THE WORLD'S MOST POWERFUL X-RAY LASER WILL DO FOR SCIENCE
DEEP UNDER MENLO PARK, California, there is a threemile-long machine operating in a tunnel that scientists are keeping colder than even some of the deepest reaches of space.