Making a metal teaspoon that melts in a cup of tea


#1

Originally published at: https://boingboing.net/2018/05/17/making-a-metal-teaspoon-that-m.html


#2

Great prank spoon.

Unless they don’t think to toss the tea afterward.


#3

Yeah, that’s right up there with the swimming pool filled with hydrochloric acid prank.


#4

Personally, I prefer the classics, like filling a donut with lye


#5

Lead has a sweet taste apparently so it’s perfect for tea really


#6

How does one dispose of a water-metal emulsion? Surely that will clog your pipes


#7

They sell moulds that actually look like spoons on Amazon. I’m surprised that this “professor” had never heard of Gallium.


#8

Actually if it’s gallium there’s no real danger.


#9

It melts but it does’t seem to mix with the water. Just pour off the water to retrieve the metal.


#10

#11

I immediately thought of Gallium as well, but wouldn’t it melt out from under your fingers at room temp? Maybe you could cast it, then cool it then really chill it and you might get away with a joke spoon (note - pure gallium appears to be non-toxic but its alloys can be very toxic - or so sayeth 10 seconds of google searching)


#12

Hot running water at 65C can give you second and third degree burns in under 5 seconds, and Field’s Metal tends to stick to skin and transfers heat rapidly (it’s a metal). I think if you are playing with this you do risk burns even if it’s just some hot tea. Cool demonstration, but play safely and respect the physics at play here.


#13

55%20PM

The guy in the video says it’s not safe for consumption but that it doesn’t dissolve in the tea, it just melts. So the tea could be safely drank as long as you separated the tea from the metal like in the video.
I wouldn’t do it, but that’s what he said.


#14

Of course he’s heard of gallium- his group made a video about it nine years ago:


Its melting point is <30C, so it’s likely to melt in your fingers before it’s able to reach a cup of tea.


#15

If it was Gallium yes, but the spoon in the video is bismuth, tin and lead.


#16

And they didn’t think to put a thermometer in that beaker while stirring? Huh. A missed opportunity there.


#17

http://samkean.com/books/the-disappearing-spoon/

ETA: In other words, it may be relatively new with this alloy, but it’s an old prank.


#18

If someone would be trying this on me, ruining my tea break and my Kabuse-cha, someone would get a proper yelling at.


#19

Ah, the perfect recipe for…

image

While the world argues over how to make the perfect cup of tea, they haven’t stopped to consider what outcome they are aiming for.


#20

There is no spoon.