How to Make Rock Candy

Picture of How to Make Rock Candy
but not just any rock candy.... This is, boulder candy...
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Step 1: Materials

Picture of Materials
Large Pot
Cotton String
Skewer Stick, spoon or something that covers the span of your jar

Step 2: Preparation

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Fill your jar with water leaving some empty space at the top. Pour this water into a pot.

Place the pot on the stove over medium heat. Heat until you start to see steam rise off the surface of the water. Now, slowly stir in sugar. Keep adding sugar until vigorous stirring does not dissolve additional sugar.

Next, pour the sugar syrup into a jar. Take care not to allow any sugar sediment to pour into the jar.

Step 3: Make Candy!

Picture of Make Candy!
Tie a long piece of cotton* string to a spoon, fork, skewer, etc. Then, measure the height of your jar and trim the string to this length. You may need to weigh your string down to keep it straight. For this, you can use anything that sinks in water - but avoid lead.

Place your jar in a place that it won't be disturbed for about a week.

After about a week, pull out your candy! If you don't see any growth within the first few days -- drain the sugar water into a pot, heat it and add more sugar. Also check that your string isn't super slippery.

If ants are a problem, place your jar on a plate of water - then add a few drops of detergent. This makes an ant moat.

Here at instructables HQ -- ants are a problem when it comes to leaving food on the counter.

*Do not use nylon or other synthetic stings as these are too slippery for candy crystal growth. Coarse cotton twine works best, providing locations for crystal growth to begin (these are called nucleation sites).

Step 4: Break Through

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My rock candy was left in the jar for too long... So, to salvage - I had to break my jar for the full effect. Wear safety glasses ;)
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RoseW220 days ago

I don't know why, but my sugar keeps coming off my stick?? I have tried many different solutions but it will not stay. Can you help me?

funny702 months ago
Can u use mio for flavoring??
DrWeird1175 years ago
Smoke it.
you can do that... then comment in a week and we will see if u lived
rock candy, damn auto correct
JenniferS24 months ago

Can you flavor/make it with kool-aid?

sector476 years ago
who wants candy!!!

Count me in!!!

I do!!
I DO!!! :D
Huntman005 years ago
Can u wash out that pot easily... my mom mite get pissed if i do this... please reply soon
as long as the sugar doesn't caramelize then it will come off with water
If it does caramelize, you can fill the pot with hot water, and the caramel will dissolve.
csk144 years ago
Can you color the candy?  Maybe put food coloring in the water or ad a fruit.
Goygar csk143 years ago
Adding food coloring or fruit gives no real problems. But to flavor the candy, it is best to add a candy flavoring or an extract of some flavor.
jeanphyl4 years ago
Wow this is new.Did u actually eat it?
ive had mine out for over 2 weeks and nothing has happened
crazygurl5 years ago
i love sean!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
crazygurl5 years ago
is it eatable?????????????
crazygurl5 years ago
tis is the fucken bomb
mae-kitty5 years ago
 KoZuEst, the pantyhose was a great idea. I tried to and it kept everything out. =D and also, if your having trouble growing the seed and or the crystal, either go out and buy rock candy then use that as the seed, or you can do what i did. Use a sugar cube. It works great lol.
if i put it in a cold area will it harden quicker and not have to wait a week?
link6055 years ago
to the author you should add a washer to the bottom of the string to keep it straight so if you make more candy you will still have a jar : - )
namraps5 years ago
Maybe I'm missing it, but I saw nothing about the amount of sugar.
trebuchet03 (author)  namraps5 years ago
Step 2

Keep adding sugar until vigorous stirring does not dissolve additional sugar.
can u make it on a skewer like you see if u buy rock candy from a store?
I followed the instructions and filled the bottle close to the top like you said, and ended up with way too much sugar water. Considering that you have to mix in twice the amount of sugar as water in order to reach the saturation point, you end up with about one and a half times as much liquid. Next time I'm only going to fill the jar a little more than half way. Another tip is to wet the string with water, then coat it with sugar, and let dry. This will attract additional crystal formation. Also, use a paper clip tied to the end of the string and keep it from touching the bottom or sides of the jar.
Jent135 years ago
To get bigger rock candy crystals after you have made the sugar syrup dip the string in it then roll it around in some sugar. Let dry. the put it in the jar. I did that and i got bigger sugar crystals because they had something to grow on and it keeps them from growing on the bottom and sides as much because it has a better texture.
dchall87 years ago
My daughter likes to buy rock candy sticks. The ones she gets have clear (no color), red, green, blue, and yellow crystals - sort of like a rainbow from top to bottom. I wonder how they do that?
ok on my next batch of rock candy i have an idea, my idea is to put a little sugar water is put half in color it, color the other half while still in the pot than carfull put it ontop so see if one will stay ontop of the other, if they do they might do it with 5 colors
KoZuEst5 years ago
A better alternative for the string would be a wooden stick. Probably something like those bamboo BBQ skewers, although bamboo might also be a bit too "slippery". I just think using a stick instead of a string makes the candy better to eat.. like a lollipop. Chewing on a piece of string is somewhat unpleasant. Also, maybe something to protect from the dust? If it needs to sit there for a week.. there will probably be some dust or dog hair in it. I don't like hair in my candy.
trebuchet03 (author)  KoZuEst5 years ago
You can dust cover as long as it allows the solution to evaporate, that is, no airtight covers (probably not plastic either) ;)
Pantyhose.. :D I know, they put jars of water covered with pantyhose in pianos to keep the humidity levels stabile.
Ummm... I think I should make some Root Beer rock candy! *drools*
brazilian sugar works?
its sweet literally! :D I need 2 make some! actually my friends made rock candy for science class, they wanted to make flavored rock candy and used kool aid instead of sugar. I guess because it was so sugary because of the kool aid it grew bigger faster! I wonder about ice tea rock candy?
yummy candy
d2j56 years ago
nice! finaly i know how to make rock candy. i have been looking all over for ideas
When would you add flavor? Before or after you make the syrup?
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