Introduction: Fluorescent Tonic Water Lamp

This Instructable will show you how to make a lamp based on the fluorescent properties of quinine, the chemical which gives tonic water its bitter taste.

Quinine is fluorescent which means it absorbs energy from light of one wavelength and then emits this energy as light of a longer wavelength. (In the case of quinine it absorbs UV light at about 350nm and emits light of about 460nm)

Thus with a UV LED and a bottle full of tonic water you can make a beautiful decorative lamp.

Step 1: Materials and Tools


A nicely shaped bottle with clear colourless glass and a cork stopper. (I found a very nice gin bottle which I thought was highly appropriate for a tonic based lamp!)

A UV LED (I used one of these, they can also be found in kids invisible UV ink spy pens!)

3 hearing aid batteries


Electrical PVC Insulation Tape

A bottle of tonic water


Junior hacksaw

Scalpel blade


Wire Clippers

Step 2: Preparing the Bottle

You will want to find a bottle you like the shape of, with a cork type stopper.

Soak the bottle in hot water for about ten minutes and peel off the label. Then scrape off the excess glue with the scalpel blade and wipe away any last bits with a cloth.

Step 3: Modifying the Cork

Glass tends to filter UV light so our LED needs to be inside the bottle to get a good level of brightness.

Place a button battery in the middle of the cork and draw round it. Using this as a guide (you want the final groove to be just big enough for the LED and batteries so that they stay in) cut the cork with the hacksaw so that you have two parallel cuts through the cork and then use the scalpel blade to cut out all the cork from inside the two cuts. This will be where the LED sits.

Step 4: Mounting the LED

Take your button cells and stack them, and wrap them in tape. Use the scalpel blade to trim any excess tape.

LEDs have a positive and negative leg. The LED will have a flat edge on one side, the leg on this side is the negative leg. Cut this leg so that there is about 3mm extending from the LED. Place the uncut leg against the stack of batteries so that the cut leg touches the top of the stack of batteries, this should be the negative terminal. Now tape the long leg to the side of the stack and bend it so that it touches the base, this should be the positive terminal. The LED should now be glowing. (To turn it off you should able to spin the LED and move the legs off the battery terminals)

Take the LED and battery stack and push it into the groove. It should sit in there nice and tight. If not cover with a layer of clingfilm to hold it in place.

Step 5: Final Steps

Fill your bottle with the tonic water and pop in the cork light assembly. Where the light hits the tonic it should glow a vibrant blue.

You should be able to see the blue glow with lights on but for the best effect dim the lights and admire your handy work :)

Sadly pictures don't do it justice, so to see it in its full glory you will just have to make one!

Any comments/questions welcome, I would love to know what you all think of this instructable.


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