Rock Candy

From GoonsWithSpoons
Jump to navigation Jump to search

Greetings! You have just entered a food thread that is also for SCIENCE, as we experiment in creating the fabulous treat known as rock candy. Many of you are aware of this wonderful candy but now rather than spend money in a store to buy it, you can spend money to MAKE it! The following information will detail on how I made my own magical sugar crystals and hopefully you can improve upon my carefully thought out design.

Retrieved from

Original thread at if you have archives.


Now pay close attention, because you will need all of these things or the experiment will end in a horrible failure:

  • 1 empty clean glass jar (the taller and skinnier the better)
  • 1 pencil
  • 1 paperclip
  • 1 piece of clean cotton string
  • 1 cup water
  • 2-3 cups granulated sugar
  • 1 time machine
  • 1 sheet of plastic wrap or wax paper
  • 1 candy thermometer (optional)

Time machine not shown:


The Candy[edit]


Ok after you've gathered all of your supplies, next comes the prep phase. Before mixing anything here is what you need to do to assemble your HI TECH crystal candy maker. First, you will want to cut a piece of the string that's a little longer than the glass is tall, just to make sure you'll have enough length to tie the knots. Second, tie one end of it to the middle of your pencil. Third, tie the other end to your paperclip. When done hang this in the jar, the string shouldn't touch the bottom. If it does, untie and retie it till it's the correct length.


Now that your device is created, head on over to your stove and boil up that cup of water like so.


You will want at least 2 of these.


After mixing it in make sure it's all dissolved, and add more sugar until you feel the water can't hold anymore.


This is where you use that candy thermometer(if you have one). You'll want this to be about 240 degrees F to ensure maximum dissolving power. If you don't have one, just do what I did and use your hand. If it burns off your flesh, it's hot enough. If you're a pussy though you can just guess. A good way to tell is by letting it come to a boil again once the sugar is added. When done you'll have this. This would be a good point to add any food coloring or flavoring that you intend to have in the final product.


WARNING! DO NOT DRINK! This stuff is VERY hot and can cause massive burning if spilled, and spill it will if you're not careful and crafty. Make sure to pour it in in small amounts at a time, so you don't crack your fancy jar like a bitch. When it's all poured in it should look like this.


Oh how did that happen.


Ok now take the string out and let it dry.


While waiting for it to dry keep the jar covered with the plastic wrap or wax paper to keep the magic sealed inside.


Ok it's dry go ahead and put it back in and put the wrap back over it so it stays sealed.


Ok now hop in your trusty time machine and go forward in time about a week. (There was a 2mb gif here of wavy lines and pretty colours. I took it out. Use your imagination.)

What the.....GOSH it grew all over the place and is stuck to the bottom!


Upon closer inspection there seems to be a fully formed crystal on the string AND the paperclip, with several bite sized super candies floating in the jar as well. There were lots of them but I ate them before I could take the pic.


All around this experiment has ended in a delicious success.

The Science of Rock Candy[edit]

FOR SCIENCE! The process behind this creation is quite simple. When heating up the water it of course increases it's capacity for dissolving shit, mostly sugar in this case. When it cools that sugar needs a place to go and starts forming crystals. If there's dry sugar in the jar at the time then an already existing crystal is a natural place for the growth to start. Most people just wet the string and pat some sugar onto it but oh no, we're more manly than that. That's why we dunk the whole thing in, then take it out and let it dry. Over the period of a few days your crystal will gain size. The longer you wait, the bigger it gets.

Next time I may just dunk the string in and THEN tie it to the paperclip once it's dry, so that I don't get a mass growing on the weight itself.

PRO TIP: If you're not getting any super crystal growth action then reboil the sugar goo and add more sugar in, dissolving as much as possible. That's what I had to do halfway through the experiment. Just be careful you don't spill any sugar bits in the jar when reheating because that's what I did and I wound up with that blob of crystals everywhere as a result.

One final note. I first attempted this with brown sugar, but after 3 weeks I had no candy. I was quite angry so in my rage I threw the sugar jar at a hive of swarming bees and then went and watched Kung Fu Hustle. Being my first experiment, I may have done something wrong. You're welcome to try this with other sugars and if you are successful please post your results.