Introduction: Things That Will Glow in Black(UV) Light

Once upon a time Ultraviolet(UV) or "black" Light was reserved for clubs, theaters and science labs.

With the arrival of cold cathode lamps and LEDs we can all have some fun.

Step 1: The Science Bit

Ultraviolet light forms part of the Electromagnetic Spectrum (first proposed by James Clerk Maxwell: Respect) which comprises (in order of increasing wavelength) Gamma Rays, X-Rays, Ultraviolet Light, Visible Light, Infrared Light Microwaves, Radio Waves.

Ultraviolet is divided into three ranges:

•UVA - “ black light“ Harmless

•UVB – causes Suntan, makes the skin produce vitamin D, Most dangerous as it can cause burns and skin cancer

•UVC – Used to Sterilize things - Not a hazard as not much occurs naturally.

Fluorescence is when some substances absorb the normally invisible UV and re-radiate it as visible light.

Step 2: Security Features in Bank Notes.

UK bank notes feature the denomination printed in Fluorescent ink. They glow with a vibrant yellow and red under UV Light.

Step 3: Credit Cards and Driving Licences.

I have blurred out the left hand image for obvious reasons . The center image is a UK driving License. The right hand shows the "MC" sprinted on all MasterCards.

Step 4: My Teeth.

Over the years I have had endless trouble with my teeth. I have had a lot of (very expensive and uncomfortable) dental prosthetic work over the last 35 years or so. Over the years the materials and technology have changed. Some of my crowns glow under UV light some don't.

Step 5: Odds and Ends

On the left is a glass of tonic water which contains quinine. Originally used by ex-pats in the British Empire as a medicine to protect against Malaria. It glows blue.

The middle picture shows Turmeric spilled on a chair. Also visible are some bits of lint glowing white.

On the right is a green circuit board which glows blue.

Step 6: Paper

Most white paper contains fluorescent dyes to make it look whiter in daylight. The picture on the left show a poster in natural light against a cream painted wall. Under UV light the wall disappears and the poster glows.

Step 7: And Finally..

I was discussing with a fellow maker (Hi Kerry) at Coventry Maker-space that Urine fluoresces. When I got home I was about to have a bath when I saw that my wretched cat Smith Pussy had obligingly done a wee on the bathroom floor. this can be seen glowing yellow as urine contains phosphorus. I shows up better when it is dry, but who wants to let cat wee dry on the bathroom floor?

I now have two new furry white slippers.*

*No cats were harmed in preparing this instructable. Yet


Krest made it!(author)2015-09-01

Live scorpions glow as well (yellowish).

potter0214 made it!(author)2015-11-07

I think it's more bluish

gigaandrew made it!(author)2015-10-09

He is right about all of these things as I am an expert on UV or "Blacklight". If you want to see a bunch more things check out my Instructable (Things that glow under blacklight). Kudos davefhunt.

BrianCrouch made it!(author)2015-09-08

I had been wondering if UV-C lights, for disinfecting surfaces, could also be used for glow in the dark experiments. Thanks!

glennell made it!(author)2015-09-03


Moose+Dr made it!(author)2015-09-02

Oh, vitamin B3 glows like crazy under black light. I had a "glow in the dark" birthday party for my daughter some years ago. I spiked the punch, the birthday cake and snacks with B3. Everything glowed wonderfully.

Aand highlighter ink glows in the dark! Many white plastics, especially cheap stuff that you get at the dollar store glow in the dark.

Moose+Dr made it!(author)2015-09-02

Hmmm, I noticed some "water" downstairs, and have wondered if it is my dog. I was planning to look up whether black light would reveal it. You answered my question -- thanks. Poor tigger ain't gonna get away with nuthin now!

zco12 made it!(author)2015-09-02

this is realy cool

jordmurph made it!(author)2015-09-02


jordmurph made it!(author)2015-09-02


PKM made it!(author)2015-09-02

I found milk/butter and olive oil also fluoresce a little, orange and green respectively so with the quinine you can have a nice spectrum. Taking my blacklight into the shared kitchen of our student house was a mistake... you know in those horror films when the crime scene investigators go into the house where the murder took place? It wasn't too far off that.

themullusk made it!(author)2015-08-28

hey your card info is visable in the black light photo, combine it with the edited pic you can get all the numbers. cool pictures though.

davefhunt made it!(author)2015-08-29

Thank you for your concern. This card was a dead one I keep for demonstration purposes. I was more concerned about Identity theft.

PKM made it!(author)2015-09-02

If you're concerned about identity theft, maybe also redact your address from the driving license photo?

jdoss2 made it!(author)2015-08-31

Some male birds glow as well.

15, 7:37 PM.jpg
radiograf made it!(author)2015-08-29

Don't forget vasaline or uranium glass, and yes it is radioactive!


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