Gray Matter

Gray Matter

Homemade Titanium

With heat and common chemicals, the author turned ore into metal

An iron crowbar costs about $8; one made of titanium, $80. Solid-titanium scissors start at $700, and don't even ask about the titanium socket wrench. Titanium must be a rare and precious substance, right?

Actually, as raw ore, titanium is 100 times as abundant as copper. Nearly all white paint is white because of the titanium dioxide found in the ore. Something like four million tons a year go into paint, sunscreen, toothpaste, even paper.

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Gray Matter

Making Glass in a Grill [With Video!]

The author creates an ornament—using his barbecue

All the components of glass can be found in two places: the beach and the laundry room. It’s possible to melt pure white-silica beach sand into glass, but only at temperatures of 3,000 to 3,500°F. Washing soda, lime or borax (a traditional laundry aid) added to the sand disrupts the quartz-crystal structure of silica and reduces the required temperature to a more practical, though still dangerous, 2,000°F, which I achieved with a backyard grill and a vacuum cleaner.

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Gray Matter

Metal's Hidden Treasure

All metal is made of crystals; you just can’t see them—without a little acid, anyway

The phrase “passing the acid test” gained popularity in the gold-rush years of the 1850s when miners used strong acids to determine whether the metal they had found was real gold or not. If it bubbled and frothed on contact with acid, it wasn’t gold. But even these failures produced something interesting and beautiful.

When pure metals cool, they solidify into intricately interlocked crystals. You can’t see the crystals because they fit together perfectly to form what appears to be a uniform mass with a smooth, solid surface. But acid can reveal the structure inside.

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Gray Matter

Make Your Own Ammo

How do you turn molten metal into perfect spheres? Just pour it off the roof

About 230 years ago, molten lead that rained from the sky—historically something to avoid at all costs—became a clever new way to manufacture an important commodity: shotgun ammo.

Precisely round pellets fly straighter, but casting each in its own 1/8-inch mold isn’t exactly mass production. In space, making them would be easy. In zero gravity, surface tension pulls any liquid into a sphere, the shape with the least surface area for a given volume.

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Gray Matter

Shattering the Strongest Glass

Explosive glass drops demonstrate why your car windshield is so strong and safe

BANG!: Break the tail of a Prince Rupert’s glass drop, and the whole thing explodes.  Mike Walker; special thanks to Glass Lake Studio
If you want a scientific display of the dangers of pent-up stress, Prince Rupert’s drops are it. After the trauma of being dropped molten-hot into a bucket of cold water, these glass balls, named for a 17th-century amateur scientist, turn into bundles of high tension. They’re impervious to even the strongest blows, until you find their hot button: Flick the tail, and they explode.

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Gray Matter

Let Burning Metals Lie

There’s not much you can do to put out a magnesium fire. Douse it with water or spray it with a fire extinguisher, and the results can even be explosive


If you ever see a large industrial metal fire (yes, they happen) on the news, you may be surprised at what the firefighters do to extinguish it: nothing. Several metals, including lithium, sodium and magnesium, can burn easily, and from time to time large amounts catch fire in factories. But even heaps of burning metal need not cause immediate panic. They don’t blow up; instead they tend to build up ash that chokes off their oxygen supply, so they slowly burn out.

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Gray Matter

The Instant Hot Tub

If a few ounces of quicklime mixed with water can make self-heating soup cans, we figured 500 pounds of it could create a self-heating hot tub

Self-heating soup sounds like something from the future: Push a button on the can, and three minutes later the contents are piping hot. But its widely available today, along with self-heating coffee and hot chocolate. In Japan, I even found self-heating sake. Pretty high-tech!

Or not. In fact, these products use a chemical reaction known since at least 4000 B.C.—the mixing of quicklime and water. When you roast limestone at about 1,650�F, it converts to quicklime, a powder used to disinfect corpses in war zones. Mix quicklime with water, and it grabs and binds the water molecules, releasing lots of energy in the form of heat. (The material left over, known as hydrated or slaked lime, is the basis of lime mortar, popular in the Roman empire and still used today.)

Soup is OK, but I decided to use the technology to make a self-heating hot tub.

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Gray Matter

Flaming Oxygen Drops

In large quantities, pure liquid oxygen is powerful enough to launch rockets. But even a tiny bit packs a wallop too

Oxygen is a good thing. Oxygen is life. But if it were much more than one fifth of our air, wed be in serious trouble. The other four fifths is nitrogen, an almost completely inert, obstructionist gas whose main effect is to get in the way of the oxygen, especially where flame is involved. For every bit of oxygen a fire consumes, it has to heat up and push away four times as much useless nitrogen. With pure oxygen, that damper is gone, and things that merely smolder in plain air go up like dry tinder. In 1967 three Apollo 1 astronauts died in a raging fire when Velcro lit up in their pure-oxygen pressurized space capsule.

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Gray Matter

Trap Lightning in a Block

To create beautiful electrical-charge patterns like this, you could use a giant particle accelerator. But shag carpeting will also do just fine. Watch how Lichtenberg figures are made in our amazing video

There are many unusual things to see around Newton Falls, Ohio—the Wal-Mart with hitching posts for Amish buggies, the Army base with helicopters and tanks proudly arranged on hills—but I was here for the most unusual thing of all: the local Dynamitron. I was here to make frozen lightning.

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Gray Matter

Titanium or Plain Ol' Steel?

Cut through titanium-marketing hype—take a grinder to your stuff

How will other materials hold up under the grinder? Launch the gallery here to find out.

In the early 1900s, the element radium was so popular, it became a marketing term. Luminous watch hands used radioactive radium, but Radium-brand butter, fortunately, did not. Today, titanium is the new radium. Everything from credit cards to crowbars is advertised as having the strength of titanium. How many products actually do?

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Gray Matter

Plate Your 'Pod

How do you keep the back of your iPod clean? Sandpaper and electricity

by Mike Walker:  Mike Walker
I think Apple sells fantastic objects that look like they came from the future. And apparently, in that future we all live in velvet rooms and have no fingers-there´s no other way to explain the ultra-shiny mirrored backside of my new iPod nano, which got scratched and grungy with fingerprints in exactly three seconds. So I gave it a nifty scuff shield and, while I was at it, my own logo, using a superthin layer of electroplated copper.

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Gray Matter

Burning Metal

Send steel up in flames—as long as it's in wool form

by Mike Walker: Hot Steel: Set a steel-wool pad ablaze using an ordinary match.  Mike Walker
I was 10 years old, but I'll never forget that day: The smell of bread in the oven. The crunchy grit of steel wool in my fingers. The fact that my mom still left matches out where I could find them. That's when I learned that, yes, you can light steel with a match.

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Gray Matter

Save a Snowflake for Decades

Create a lasting cast of nature´s perfect crystals with a drop of chilled superglue

Preserving a Snowflake in Superglue

Cost: $10
Time: 10 minutes
Easy | | | | | Hard


How It Works

  1. Set microscope slides, coverslips and superglue outside when it's snowing



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