So far in this series, we’ve talked about man-made byproducts — Fordite, which is built-up layers of cured car enamel, and Trinitite, which was created during the first nuclear bomb test.

But not all byproducts are man-made, and not all of them are basically untouchable. Some are created by Mother Nature, but are nonetheless dangerous. I’m talking about fulgurites, which can form whenever lightning discharges into the Earth.

It’s likely that even if you’ve seen a fulgurite, you likely had no idea what it was. So what are they, exactly? Basically, they are natural tubes of glass that are formed by a fusion of silica sand or rock during a lightning strike.

Much like Lichtenberg figures appear across wood, the resulting shape mimics the path of the lightning bolt as it discharged into the ground. And yes, people make jewelry out of fulgurites.

Lightning Striking Again

Lightning is among the oldest observed phenomena on Earth. You probably know that lightning is just a giant spark of electricity in the atmosphere. It can occur between clouds, the air, or the ground and often hits tall things like skyscrapers and mountaintops.

Lightning is often visible during volcanic eruptions, intense forest fires, heavy snowstorms, surface nuclear detonations, and of course, thunderstorms.

In lightning’s infancy, air acts as an insulator between charges — the positive and negative charges between the cloud and the ground. Once the charges have sufficiently built up, the air’s insulating qualities break down and the electricity is rapidly discharged in the form of lightning.

When lightning strikes, the energy in the channel briefly heats up the air to about 50,000 °F, which is several times the surface of the Sun. This makes the air explode outward. As the shock wave’s pressure decreases, we hear thunder.

Of Sand and Rock and Other Stuff

Fulgurites, also known as fossilized lightning, don’t have a fixed composition: they are composed of whatever they’re composed of at the time of the lightning strike. Four main types of fulgurites are officially recognized: sand, soil, caliche (calcium-rich), and  rock fulgurites. Sand fulgurites can usually be found on beaches or in deserts where clean sand devoid of silt and clay dominates. And like those Lichtenberg figures, sand fulgurites tend to look like branches of tubes. They have rough surfaces comprised of partially-melted grains of sand.

When sand fulgurites are formed, the sand rapidly cools and solidifies. Because of this, they tend to take on a glassy interior. As you might imagine, the size and shape of a fulgurite depends on several factors, including the strength of the strike and the depth of the sand being struck. On average, they are 2.5 to 5 cm in diameter, but have been found to exceed 20 cm.

Soil fulgurites can form in a wide variety of sediment compositions including clay-, silt-, and gravel-rich soils as well as leosses, which are wind-blown formations of accumulated dust. These also appear as tubaceous or branching formations, vesicular, irregular, or a combination thereof.

Calcium-rich sediment fulgurites have thick walls and variable shapes, although it’s common for multiple narrow channels to appear. These can run the gamut of morphological and structural variation for objects that can be classified as fulgurites.

Rock fulgurites are typically found on mountain peaks, which act as natural lightning rods. They appear as coatings or crusts of glass formed on rocks, either found as branching channels on the surface, or as lining in pre-existing fractures in the rock. They are most often found at the summit or within several feet of it.

Fact-Finding Fulgurites

Aside from jewelry and such, fulgurites’ appeal comes in wherever they’re found, as their presence can be used to estimate the number of lightning strikes in an area over time.

Then again there’s some stuff you may not necessarily want to use in jewelry making. Stuff that can be found in the dark, dank corners of the Earth. Stay tuned!

This week on the Podcast, Hackaday’s Elliot Williams and Kristina Panos joined forces to bring you the latest news, mystery sound, and of course, a big bunch of hacks from the previous week.

First up in the news: we’ve extended the 2024 Supercon Add-On contest by a week! That’s right, whether you were held up by Chinese fall holidays or not, here’s your chance to get in on this action.

We love to see the add-ons people make for the badge every year, so this time around we’re really embracing the standard. The best SAOs will get a production run and they’ll be in the swag bag at Hackaday Europe 2025.

What’s That Sound pretty much totally stumped Kristina once again, although she kind of earned a half shirt. Can you get it? Can you figure it out? Can you guess what’s making that sound? If you can, and your number comes up, you get a special Hackaday Podcast t-shirt.

Then it’s on to the hacks, beginning with what actually causes warping in 3D prints, and a really cool display we’d never heard of. Then we’ll discuss the power of POKE when it comes to live coding music on the Commodore64, and the allure of CRTs when it comes to vintage gaming. Finally, we talk Hackaday comments and take a look at a couple of keyboards.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download in DRM-free MP3 and savor at your leisure.

Episode 293 Show Notes:

News:

• Breaking News: 2024 Supercon SAO Contest Deadline Extended

What’s that Sound?

• Know that sound? Submit your answer for a chance at a Hackaday Podcast T-Shirt.

Interesting Hacks of the Week:

• What Actually Causes Warping In 3D Prints?
  • A Technique To Avoid Warping On Large 3D Prints
• Have You Heard Of The Liquid Powder Display?
• A Phone? A Ham Radio? Relax! It’s Both!
• Symbolic Nixie Tubes Become Useful For Artistic Purposes
• Linus Live-Codes Music On The Commodore 64
• Are CRT TVs Important For Retro Gaming?
  • Pixel Art And The Myth Of The CRT Effect

Quick Hacks:

• Elliot’s Picks:
  • Arduboy Cassette Award Explores New Features
  • An Arduino Triggers A Flash With Sound
  • Your Battery Holder Is Also Your Power Switch With ToggleSlot
• Kristina’s Picks:
  • Mapping A Fruit Fly’s Brain With Crowdsourced Research
  • Portable Pi Palmtop Provides Plenty
  • Using The 555 For Everything

Can’t-Miss Articles:

• If You Can’t Say Anything Nice
• Keebin’ With Kristina: The One With The Folding Butterfly Keyboard

Want to give prospective employers a business card that doesn’t immediately get tossed? Of course you do. If you’re one of us, the answer is obvious: make it some kind of a PCB.

[Ricardo Daniel de Paula] initially chose the CH32V303 microcontroller because it has native USB 2.0 and 16 capacitive touch channels, which can support up to 48 keys via multiplexing.

But in order to reduce costs, [Ricardo] switched to the CH582M, which does all that plus Bluetooth communication. The goal is to have an affordable design for a unique, functioning business card, and I would say that this project has it in spades.

Btrfld is a Folding Butterfly Keyboard

This origami beauty’s name is pronounced ‘butter-fold‘, by the way. And that’s because this is a folding, portable version of the original butterfly keyboard by [SolidusHal]. Be sure to check out the .gif of it folding and unfolding on the first link.

As [SolidusHal] says over on GitHub, there aren’t any amazing sources of ULP keycaps yet, so the best option is to print them, and of course you’ll find the STLs in the repo. But beware, an FDM printer isn’t up to this task.

While you could hand-wire this thing, board files are available, so you should probably use them if you’re gonna build your own. And controller-wise, you can use a nice!nano or a BlueMicro840, or just a Pro Micro if you don’t want Bluetooth.

The Centerfold: Taste the Rainbow

Do you rock a sweet set of peripherals on a screamin’ desk pad? Send me a picture along with your handle and all the gory details, and you could be featured here!

Historical Clackers: Salter No. 5

The curved keyboard of this Victorian beauty isn’t just for looks — it was designed to mimic the shape of the hands and thus be more comfortable.

What you can’t do with this one is slouch in your chair, otherwise you won’t see what you’re typing over that curved, black shield in the middle.

It is thought that there were no Salter nos. 1-4, and that Salter started with a higher number as to appear more established. Although sold by George Salter’s family company, the typewriter was invented by James Samuel Foley in 1892.

The Salter no. 5 features a three-row keyboard with two Shifts, one for upper case and the other for figures. Altogether, there are 28 keys that can produce 84 characters.

While early 5s used an ink pad, the later models employed a ribbon. They were marketed to compete with Remington typewriters and such, but at one-half or one-third the cost. Even so, they were one of the best typewriters available at the time.

ICYMI: KanaChord Plus Makes Comprehensive Japanese Input Simple

Have you ever wished you had a separate, smaller keyboard for inputting another language so you didn’t have to switch up your OS every time? Well, then KanaChord Plus is the keyboard for you, as long as your second language is Japanese.

As you may have guessed, KanaChord takes chording input — pressing multiple keys at once as you would on a piano. It uses color in order to indicate character type, Kana mode, and even to provide error feedback. Worried that it won’t work with your OS? There’s a slide switch to select one of three Unicode key sequences. Guess which three.

The touch screen is the icing on this updated cake. As you chord, an incremental Input Method Editor will search the embedded dictionaries and display an ordered list of Japanese words and Kanji choices to scroll through and select. [Mac Cody] has plans to support the Pico 2 and will update the comprehensive repo when it’s ready.

Got a hot tip that has like, anything to do with keyboards? Help me out by sending in a link or two. Don’t want all the Hackaday scribes to see it? Feel free to email me directly.

We love to watch your projects grow as much as you do. Really, we’re like proud grandparents around here. So it’s great to see that [Mac Cody] is back with the KanaChord Plus Keyboard, which supports an astounding 6,165 Kanji as well as 6,240 of the most common Japanese words that contain Kanji. This is all in addition to supporting the Kana characters, which make up the rest of Japanese writing (more on that in a minute).

If you need to input Japanese, this is a dream come true. If you’re trying to learn Japanese in the first place, this could be exactly what you need to become fluent.

Without getting into it too much, just know that the Japanese writing system is made up of Kanji, which are Chinese characters, Hirigana, and Katakana. The latter two are collectively known as the Kana, and there’s this table that lays out the pairing of vowels and consonants. For [Mac Cody], it was this layout that inspired this chording keyboard that covers all three.

What this keyboard actually does is generate Unicode macros to render Japanese characters using chords — pressing multiple keys at once as you would on a piano. The most obvious improvement aside from the huge gain in characters is the display.

As with the original KanaChord, one of the great features of the KanaChord Plus is that it uses color in order to indicate character type, Kana mode, and even provide error feedback. Another is the slide switch that selects one of three Unicode key sequences in order to support different computer platforms.

But the touchscreen display is the addition where things get really interesting. As Kana are typed, an incremental Input Method Editor (IME) searches the embedded dictionaries to display an ordered list of Japanese words and Kanji that the user can scroll through and select.

Just like the original, the brains of this operation is a Raspberry Pi Pico. [Mac Cody] used an Adafruit NeoKey 5×6 Ortho Snap-Apart keyboard PCB and 30 Cherry MX switches that we choose to believe are blue. Looking toward the future, [Mac Cody] plans to support the Pico 2, and will update GitHub when everything is ready. Again, there’s a ton of detail in the hardware section, so be sure to check that out.

What is with all the wasted space on keyboards? There’s a whole back side just sitting there doing nothing. But how can you use the back at the same time as the front?

Just when we think Google Japan can’t possibly produce another weird, amazing keyboard that actually works and comes with full documentation, they go and outdo themselves with this ortholinear Mobius thing that wastes (almost) no space. (Japanese, translated) Be sure to check out the video after the break where hilarity ensues.

This crazy thing is made up of 26 modules, each with 8 key switches, four on a side. Do the math — that’s a total of 208 keys! More than enough to stretch out around the table and do some group programming without rubbing elbows. All the switches are hot-swappable, and there’s even RGB backlighting. The controller here is the STM32F042F4P6.

So what are all the extra keys for? Well, the keyboard is half in Japanese and half QWERTY, and has a set of emoji keys as well for the full programming experience. You can also make a paper version if you want to test out the topology.

Be sure to check out the documentation, because it’s pretty interesting how this keyboard is put together. And no, we’re not sure how to set it down and use it without accidental key presses. Suppose that’s part of the charm?

Have you ever wondered what happened to all the Japanese computers of yore? We did.

Thanks for the tip, [CityZen]!

So, we heard you like SAOs. How about some SAOs for your SAO? That’s exactly what’s going on here with [davedarko]’s SAOAO — introducing the Supercon Add-On Add-On standard, which is inspired by another minibadge standard by [lukejenkins]. At most, an SAOAO is 19×19 mm and features a 1.27 mm 3-pin header. As [davedarko] says, no pressure to do I²C, just bring the vibes.

All SAOAOs use the Yo Dawg SAO baseplate, which has room for three SAOAOs. Because six pins is often too many to make a few LEDs light up, the SAOAO standard uses a mere three pins. Not only are SAOAOs easier to route, the pins can’t even be mirrored accidentally because VCC is in the middle, and both outside pins are grounds.

Want to get your hands on some of these bad boys? [davedarko] is bringing 100 Yo Dawg SAO baseplates and 200 SAOAOs to Supercon. But if you want to make your own, you are more than welcome to do so.

Today, you likely often authenticate or pay for things with a tap, either using a chip in your card, or with your phone, or maybe even with your watch or a Yubikey. Now, imagine doing all these things way back in 1998 with a single wearable device that you could shower or swim with. Sound crazy?

These types of transactions and authentications were more than possible then. In fact, the Java ring and its iButton brethren were poised to take over all kinds of informational handshakes, from unlocking doors and computers to paying for things, sharing medical records, making coffee according to preference, and much more. So, what happened?

Just Press the Blue Dot

Perhaps the most late-nineties piece of tech jewelry ever produced, the Java Ring is a wearable computer. It contains a tiny microprocessor with a million transistors that has a built-in Java Virtual Machine (JVM), non-volatile storage, and an serial interface for data transfer.

While it might be the coolest piece in the catalog, the Java ring was just one of many ways to get your iButton. But wait, what is this iButton I keep talking about?

In 1989, Dallas Semiconductor created a storage device that resembles a coin cell battery and uses the 1-Wire communication protocol. The top of the iButton is the positive contact, and the casing acts as ground. These things are still around, and have many applications from holding bus fare in Istanbul to the immunization records of Canadian cows.

For $15 in 1998 money, you could get a Blue Dot receptor to go with it for sexy hardware two-factor authentication into your computer via serial or parallel port. Using an iButton was as easy as pressing the ring (or what have you) up against the Blue Dot.

Indestructible Inside and Out, Except for When You Need It

Made of of stainless steel and waterproof grommets, this thing is built to be indestructible. The batteries were rated for a ten-year life, and the ring itself for one million hot contacts with Blue Dot receptors.

This thing has several types of encryption going for it, including 1024-bit RSA public-key encryption, which acts like a PGP key. There’s a random number generator and a real-time clock to disallow backdating transactions. And the processor is driven by an unstabilized ring oscillator, so it constantly varies its clock speed between 10 and 20 MHz. This way, the speed can’t be detected externally.

But probably the coolest part is that the embedded RAM is tamper-proof. If tampered with, the RAM undergoes a process called rapid zeroization that erases everything. Of course, while Java Rings and other iButton devices maybe be internally and externally tamper-proof, they can be lost or stolen quite easily. This is part of why the iButton came in many form factors, from key chains and necklaces to rings and watch add-ons. You can see some in the brochure below that came with the ring:

The Part You’ve Been Waiting For

I seriously doubt I can get into this thing without totally destroying it, so these exploded views will have to do. Note the ESD suppressor.

So, What Happened?

I surmise that the demise of the Java Ring and other iButton devices has to do with barriers to entry for businesses — even though receptors may have been $15 each, it simply cost too much to adopt the technology. And although it was stylish to Java all the things at the time, well, you can see how that turned out.

If you want a Java Ring, they’re on ebay. If you want a modern version of the Java Ring, just dissolve a credit card and put the goodies in resin.