This rock is so cool! Download TEMU App to get $100 coupon bundle: temu.to/m/ugsqs5t685d Or Search my code [dkm5733] to claim the offer!!（for all users）

How does it taste tho

Ohh no! Not Temu!

The term "television stone" reminds me of "slow glass"; an idea in a science fiction story, 'The Light of Other Days' (1966) by Bob Shaw, in which there is glass through which light travels so slowly it allows you to see back in time!

When you broke the TV stone all I could think was: reminds me of asbestos, hold your breath, don't breathe in the fibers.

Please dont Support temu. Its realy not good .

5:50 Temu are the Spam Kings

There is a company that fuses a bundle of fiber optic strands, heats them up and stretches the middle, then cuts them at the thin point. After this the polish the ends and it does the same thing, but scales the image. Due to the fact that the light is amplified with the same ratio the image doesn't get dim. No idea if they are still made, but looked like magic

And thanks to vsauce I know the coolest thing this rock can do: show you the sun even through heavy clouds. because the sun's light is parallel there'll be a brighter area visible on the stone when you point it at the sun, than when you point it at any of the diffuse light that the rest of the clouds have

"they do *feel* cheaper, and that's because they *are* cheaper" i lost it

I appreciate the pace of your videos because their basically always like "Ok yeah but why?" and then you go one layer deeper, and deeper. Always learn a lot watching them.

sorry but disliking for promoting TEMU!!

1:30 "Look at this cool rock. Now let's smash it!" 😅

Imagine a box of Legos made out of this, and needing to walk across the floor after dropping the box.

I've had a chunk of this stone for 25 years. I never once knew about the laser property. Awesome!

1:25 "They're actually hair-like fibers" *Smashes asbestos

I'm a design engineer, quite into physics. Most KZfaq channels cover things either too basic and known to me or are purely technical but without much fun. You, Sir, manage to amaze me with your amazing little experiments and "magic" materials! Thank you!

"The sky is falling!" "It hit me on the head, and it looked like a stop sign!"

My brain: why don't we use this stuff for phone screens? Action lab: (whacks stone with wooden dowel and shatters it into a million pieces) My brain: "fair enough"

video was great up until 4:53

When he started to break it, my mind went NOOO for a second

Cool stuff. I work with similar but tapered fiber optic blocks to optically couple an x-ray scintillator screen to an array of camera chips. It's pretty amazing the amount of resolution we can get out of such blocks.

Bro took a sponsorship from worlds leading child labour supporters

Really captivating demonstration of ulexite's optical properties and total internal reflection. It's fascinating how nature has had its own version of a 'fiber optic cable' all along.

Television stone sounds like a funny name. I wonder why they did not call it a chameleon rock. 😂

The most interesting mineral arrangement I've had explained to me ever. Very well done!

A big unknown: why someone that investigates all these subjects doesn't do the same with the sponsors?

I'm a nerd and I studied engineering and yet... yet... I always learn so much from your quick and simple lab stuff, so glad you're inspired to share it (I'm sure KZfaq revenue helps but I can tell you just genuinely love it)

I imagine if they can grow this synthetically there'd be SOME sort of application with it and screens. Screens in bathroom tiles or kitchen counters or something.

Never knew about this television stone - absolutely fascinating and mega cool! Thank you for sharing!

Is it a dangerous cristal (maybe because of the cristaline fibers) like asbestos is?

In my 13 years working in an optical shop, we never called the angle at which total internal reflection occurs the "critcal angle". We called it the Brewster's Angle, and it is specific to any two adjacent optical media. For super nerds, the angle is equal to arctan(n2/n1), where n2 and n1 are the Indices of Refraction of the outside media and inside media.

One thing you said wrong. Critical angle is not “ when 100% light gets reflected”. It is when the angle of refraction is 90 degrees. Light rays just move on the surface touching it. Most of the light gets reflected. Above critical angle, be it even 1 degrees, then it gets completely reflected what we call 100% reflected. Correct me if I’m wrong.

I noticed something about a month ago that I wanted to tell you about. The vent below my dash has a white circle with a white X inside of it. When I saw the reflection of this in the window of my door that was half way open the white circle had a white + inside of it. Some how the curve of the window is just right to rotate the reflection 45 degrees.

Damn... Soul sold... -.-

your analogies are fantastic, it makes the subject matter attainable

1:30 I was like "don't break it"!

One of the most interestinf episodes! I wonder if this rock has any use appart for doing experiments with it. It's amazing how the Earth can form such perfect rock!

It’s so weird to me that the circles are perfect coming through the stone. Literally perfect

The slinky demonstration was brilliant! Action lab and Steve Mould are great at intuitive analogous demonstration

I have a few pieces of this. Bought some from a shop about 5 years ago. Very cool

I’m gonna call it reality fragment as it’s basically a piece of reality that was shattered and can be placed on anywhere in space to merge onto such existential object

Bro, please don't promote this BS site. It's the epitome of cheap consumerism culture. Please don't promote it.

"This stone is so incredible." [smashes it]

Oh man this has a lot of potential for cool decorations

Never seen one of those before. Very cool !!

6:08 Temu also say you have to buy at least £10.00 of stuff, because of delivery costs, and is Paid for by the USA I hear

Really like these videos when you break down complex ideas with something I never knew existed

This is soo neat. Your channel is always so Informative and fun! 👍

That stone looks more like satin spar selenite to me. Both selenite and ulexite are very similar with all properties mentioned in this video, but selenite is more common, cheaper, and often whiter than the yellowish ulexite.

This looks like a material you would *not* want to inhale.

Nice demonstration of optics!

I have one of these inside my computer case- I got it at the top of Pike's Peak, it's really neat- it doesn't magnify, it projects what's on the bottom to the top.

So in a random galaxy, in a random planet there could be this stone scattered throughout the planet so those aliens could spy on other countries with this stone...

I've actually been thinking about this material for a while now 🤔‼ I wonder if we could make an "orthographic camera lens" out of it. It wouldn't be a lens in the traditional sense since it doesn't focus any light, but given it's optical properties it would still filter out light by its incoming angle - the angle in question being a precise 90°, ideally speaking, making the resulting image perfectly orthographic. Randomly incoming light hitting a light sensitive screen would usually produce no image at all or a very blurry one, depending on the exact setup, but by using this "lens"/ filter, we effectively eliminate blur, which means we should be able to produce sharp images. The image would obviously be restricted and limited by the image sensor shape and size, and the exposure time would likewise vary wildly depending on the type of image sensor and its sensitivity, but I imagine some sort of polaroid-like film would be sufficient to make this a fun experiment. I'm not sure if there are any practical use cases for such a lens, especially given its sensor limitations, but I think something like this could have potential in microscopy, where (I'd assume) the electronic image sensors are as small as phone cameras' anyway, small scale telescopes for astrophotography, other fields in which small image sensors are used or maybe even laser technology

The slinky thing is such a smart and clever example!

I had a tie tack and finger ring made out of polished fiber optic cable. It was pretty cool to look through.

I think angling the camera would have been a great way to show how the light was coming from the *top* of the stone.

Sorry but temu's labor practices are questionable.

This is one of your better efforts. Fascinating, and previously unknown.

1:09 I thought that was a giant screen you were calling your phone but after watching a few times I realized you just covered it with a fabric lol

the real fiber optic cable core

I wonder if you could make one out of stacking a bunch of super thin fiber optic cables together? Less optical defects..

Those crystal fibers wouldn't float around in the air like asbestos does because they are heavier also if you were to breath it in you mostlikely would not be able to breath in enough before you had some reaction to it like coughing up gunk or your throat hurting. Like with asbestos it takes time and consistent exposure to get to the point of it hurting you not just one inhale. Also why don't we make a lense out of it for projectors. It would make a projection more clear by lining up the light going through it.

Okay the slink demo is so awesome!

So this is how cavemans watched the football matches... I see!

This is really cool, would there be any way to make it work if it wasn't directly touching the surface? Like a sort of orthographic camera?

Again what a good video ! thank you for te content🤗🤗. I hope that after the lulexite you will be talking about the optical calcite which also has good features 😉

Wow, this is amazing! I did not know that kind of stone existed.

I feel smarter after each of your videos man... Thanks bro keep it up

Always exposed cool stuff on this channel, actually I am in the process of starting a business that was inspired by your videos on refractive indexes. Specifically the video where you drilled a hole in clear ice, put some water in it and put your finger in it to make it look like your finger was frozen solid.

I had one as a kid, loved that thing 👍

I didn't believe you at first, I thought this was going to be a debunk of a viral subject. Really cool. I want one!

Aristocrat slot machines use this tech on their button panels. A 1" piece of what looks like glass that sits on a small lcd screen. This magnifies the image and also makes the image appear on top of the piece of 'glass' just like the stone in the video.

I have never heard of that stone before, but suddenly I need some lol!

what is the software that you are using to show the ray tracing ?

Wow, the video description is literally just about the advertiser, would be nice to at least mention what the video is about.

Dude that slinky was such a great visual example. Thanks for making great, entertaining and educating videos! God bless.

How good could we make this synthetically? If we could make really small glass fibres and combine them into a block would the effect be much better? This reminds me of devices for creating laminar flow, lots of tubes combined together in the same orientation to direct the fluid and try to get it going straight.

Aaaah, I hoped you would get a fiber optic block, which shows the same property - it's a ~1 inch cylinder filled with straight FOs that makes perfect reproduction of what's under.

Television stone works when you hit it against a flat surface. All the spirits in the cemetery will be enticed to come along.

Why are you taking money from scams ?

this guy taught me about light in detail and with examples within 2 minutes, but my school takes about 1 month at least to teach this

I had a chunk about that same size, as a kid. I have no memory of where I got it, but I loved that thing

"it's as though it's a tv screen, but really it's a bright green stone that i'm putting an overlay on. This April Fools joke is sponsored by..."

I was about to give this video a like, but then you had a Temu advert. I cannot support their questionable business practices. I am frankly appalled a science channel I respect like you, would take a sponsorship from any of these companies.

This is an amazing material. Would love to see more on how it is formed. What kind of geology creates a parallel bunch of fibers?

With the cube of glass, you can see light coming in the sides and shadow, this confirms to me what's happening with that rock, as it has no such light coming in the sides..

I‘m sorry but he’s lost me at that sponsorship. Thought he’s better than that

This video sponsored by the CCP!

I have a chunk of that someplace... very cool rock.

I assumed this stuff was rare and expensive, but I'm holding a big block of it in my hands right now because it was so cheap! Thanks for showing me this, I'm having lots of fun with it!

Your choice of sponsors is appalling lately.

fun fact: it’s physically impossible to move without relying on other matter or without losing mass

@3:15 You don't really need the laser, you can see the light passing through it to your camera only at certain angles, and you can see surfaces mirroring. The laser is a nice additional touch, though.

I love this channel. He always has these cool ideas and can get his hands on some cool stuff! Amazing content!! Thanx for the knowledge bro! We appreciate ya✌🏻

with every ad this channel looses some of its value...

Can I get a hoooyaaaah

Thanks for helping me study for my Optical Mineralogy class :)

Hmmm if light entering the small "needles" inside form rings (due to the crystal not being symmetric and having multiple direction-dependent refraction indices) then shouldn't the transmitted image on the other side look different & distorted instead of looking like a TV screen?