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Make Rock Candy yourself

 
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sunnye



Joined: 26 Jul 2008
Posts: 5

PostPosted: Tue Feb 24, 2009 9:52 am    Post subject: Make Rock Candy yourself Reply with quote

Making your own rock candy is a fun and tasty way to grow crystals and see the structure of sugar on a big scale.
Materials :
3 cups sugar (sucrose) ,1 cup water ,clean glass jar ,cotton string ,pencil or knife ,food coloring (optional) ,1/2 tsp to 1 tsp flavoring oil or extract (optional) ,Lifesaver candy (optional) ,pan ,stove or microwave
Steps:
1,Pour the sugar and water into the pan.
2,Heat the mixture to a boil, stirring constantly. You want the sugar solution to hit boiling, but not get hotter or cook too long. If you overheat the sugar solution you'll make hard candy, which is nice, but not what we're going for here.
3,Stir the solution until all the sugar has dissolved. The liquid will be clear or straw-colored, without any sparkly sugar. If you can get even more sugar to dissolve, that's good, too.
4,If desired, you can add food coloring and flavoring to the solution. Mint, cinnamon, or lemon extract are good flavorings to try. Squeezing the juice from a lemon, orange, or lime is a way to give the crystals natural flavor, but the acid and other sugars in the juice may slow your crystal formation.
5,Set the pot of sugar syrup in the refrigerator to cool. You want the liquid to be about 50F (slightly cooler than room temperature). Sugar becomes less soluble as it cools, so chilling the mixture will make it so there is less chance of accidentally dissolving sugar you are about to coat on your string.
6.While the sugar solution is cooling, prepare your string. You are using cotton string because it is rough and non-toxic. Tie the string to a pencil, knife, or other object that can rest across the top of the jar. You want the string to hang into the jar, but not touch the sides or bottom.
7,You don't want to weight your string with anything toxic, so rather than use a metal object, you can tie a Lifesaver to the bottom of the string.
8,Whether you are using the Lifesaver or not, you want to 'seed' the string with crystals so that the rock candy will form on the string rather than on the sides and bottom of the jar. There are two easy ways to do this. One is to dampen the string with a little of the syrup you just made and dip the string in sugar. Another option is to soak the string in the syrup and then hang it to dry, which will cause crystals to form naturally (this method produces 'chunkier' rock candy crystals).
9,Once your solution has cooled, pour it into the clean jar. Suspend the seeded string in the liquid. Set the jar somewhere quiet. You can cover the jar with a paper towel or coffee filter to keep the solution clean.
10,Check on your crystals, but don't disturb them. You can remove them to dry and eat when you are satisfied with the size of your rock candy. Ideally you want to allow the crystals to grow for 3-7 days.
11,You can help your crystals grow by removing (and eating) any sugar 'crust' that forms on top of the liquid. If you notice a lot of crystals forming on the sides and bottom of the container and not on your string, remove your string and set it aside. Pour the crystallized solution into a saucepan and boil/cool it (just like when you make the solution). Add it to a clean jar and suspend your growing rock candy crystals.
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rachard1583



Joined: 01 Jul 2010
Posts: 10

PostPosted: Thu Jul 01, 2010 5:54 pm    Post subject: Reply with quote

Well, let me add some science to the topic dude, the crystals on your string should be clearly defined, with sharp right angles and smooth faces of various sizes. In the field of crystallography, these are called monoclinic crystals. Their shape is determined by the way the individual sugar molecules fit together, which is similar to the way the shape of a pile of oranges is determined by the shape of the individual oranges and the way they stack together.
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Mini Duckie



Joined: 07 Oct 2010
Posts: 3

PostPosted: Thu Oct 07, 2010 1:54 pm    Post subject: Reply with quote

This is so cool! Thanks for the recipe! Smile
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Lillatoni



Joined: 28 Oct 2010
Posts: 4

PostPosted: Thu Oct 28, 2010 8:57 pm    Post subject: Reply with quote

Rock candy is one of those old time candies that my grandfather talked about all the time from his childhood. I used to make it all the time with him when I was a kid. It was so fun watching the crystals form. Not only do you get a tasty treat, but it's a little science experiment too!
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backlashforblow



Joined: 16 Aug 2011
Posts: 1

PostPosted: Tue Aug 16, 2011 8:32 am    Post subject: Reply with quote

hey i need your help......Can i put the rock candy mixture into the oven to speed it up? Teasing
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Dilbert



Joined: 19 Oct 2007
Posts: 1008
Location: central PA

PostPosted: Tue Aug 16, 2011 12:10 pm    Post subject: Reply with quote

a warm place would speed up the evaporation - but "movement" will stunt the crystal growth. it should not be "disturbed" while growing.
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msus3380



Joined: 09 Sep 2011
Posts: 1
Location: pensacola, fl

PostPosted: Fri Sep 09, 2011 2:21 pm    Post subject: Reply with quote

Rock candy is an awesome creation to try. It is especially fun if you have young children who can be a part of the process and then enjoy the results. One thing that is mentioned above but that I've learned the hard way is that it is crucial to keep it still and unbothered while growing. Got to tell the little ones to keep their hands off while it is "getting ready". Yummm...
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