How to crack marbles DIY tutorial
Do you love the look of crackle marbles? Have you ever wondered how to make them yourself? It’s actually a lot easier than you might think!
In this tutorial, we will show you how to bake marbles in order to create that beautiful crackled effect. We’ll give you some tips on how to get the best results, and show you some cool examples to help you get inspired.
So gather up your supplies and let’s get started!
How to make amazingly awesome cracked marbles at home
One of the best things about fried marbles (also known as crackle marbles) is that they are so easy to make.
With just a little bit of simple science, you can transform any glass marbles into ones that have stunning patterns of cracks inside.
This activity can be done at home as a fun family activity or in a school setting where there is access to an oven and running water.
Who is this crackle marbles activity good for?
Because making cracked marbles is so straightforward, anyone can do it!
It makes a great science experiment for kids too, as it gives the opportunity to learn about how sudden temperature changes can affect different materials.
However, this baking marbles experiment involves very hot temperatures, so children definitely need to be closely supervised by an adult throughout.
We also recommend the use of protective clothing such as oven gloves, and that you wear safety goggles too.
What do you need to make fried marbles?
The most obvious item needed for this activity is some glass marbles. They must be made of glass, but can be pretty much any colour or size.
Bear in mind that large marbles will take longer to heat up all the way through than small ones.
Here’s a full list of the essential tools and materials needed for baking marbles:
- Marbles (clear or any colour)
- Ice cubes
- Heatproof bowl
- A container to bake the marbles in (e.g. muffin tin, cast iron skillet, pie plate or oven tray)
Note that once you have made cracked marbles they are not suitable toys for children due to the risk of them cracking completely and creating dangerous shards of glass.
How to crack marbles: step by step
To make your own fried marbles at home, just follow these easy-to-understand instructions.
This tutorial will show you the oven method for cracking marbles. Although there are other ways to heat marbles, we find the oven method the safest and most reliable one.
Some people prefer to heat the marbles on the stove, and this can also work. However, you may find it a little more difficult to heat them evenly.
- Take the marbles you want to crack and place them on an oven tray or other suitable oven-proof dish. Make sure the tray is easy to hold as later on you will need to remove it from the oven and pour the marbles directly from it into a bowl.
- Lay out the marbles evenly on the tray. They can be touching, but should only be a single layer deep.
- Preheat the oven to around 400 degrees Fahrenheit (180 degrees Celsius).
- Place the marbles inside and bake for around twenty minutes.
- Prepare a large bowl of very cold water. Add a handful of ice cubes to help cool it further (at least a few ice cubes).
- Carefully remove the heated marbles from the oven using oven mitts and wearing safety goggles. Remember they will be very hot.
- Pour the marbles straight into the bowl of ice water, being careful to avoid any splashes. You’ll want to do this on a hard surface that is heat-resistant, such as a tile floor or other hard floor, or a highly heat-resistant kitchen worktop. Make sure the marbles are fully submerged.
- Leave them in the water for a few minutes.
- Having been brought to a high heat and cooled rapidly, the marbles will become crackled on the inside as a result of thermal shock. Result!
- Drain the water and remove the marbles. Take care in case any marble has split and shed small pieces of glass. There is always a chance that some may break. An adult should do this for children and carefully check the marbles before letting children touch them. You’ll also want to take care when you drain the water too, as it will have warmed up somewhat.
Do I need to use ice water to make crackle marbles?
The short answer to this is, yes.
The cooler the water, the more drastic the cooling effect. This is what helps to give the marbles those beautiful cracks on the inside.
Cold water straight from the tap may work, but ice water is optimal. If you don’t have ice cubes, you can cool your bowl of water in the freezer or fridge whilst the marbles are being baked.
How hot should my oven be?
We suggest 400F (180C) as this works well for most ovens. However, the hotter the oven, the more cracks you will get in your marbles.
This is because that more significant temperature change leads to a stronger thermal shock and more cracking.
However, bear in mind that the higher the temperature, the greater the likelihood that a marble will break and shed shards of glass, so if you are doing this with children you may want to stick to lower temperatures.
Why does baking marbles crack them?
This cool trick all comes down to some simple science.
Putting the glass marbles in the oven heats them to a high temperature. This causes them to expand.
When you take the marbles out of the oven and place them suddenly in cold water, the marble cools down very quickly and contracts (shrinks) back down.
Because the outside cools down faster than the inside due to the very cold ice water, this causes cracks to form on the inside.
Luckily the outside of the marble is smooth to the touch, which makes it safe to hold and examine further once it has cooled down enough!
How can I crack marbles as a kids’ experiment?
This fun temperature-based activity makes a great science experiment for kids.
It gives them the chance to explore the effects of temperature changes of different materials.
You can also use it as an opportunity to teach them about how to conduct a proper scientific experiment.
For example, they can make a hypothesis by predicting what they think will happen to the marbles.
They can also repeat the process using different oven and water temperatures to compare the results.
Kids should find that the hotter the oven and the colder the water the greater the chance of creating amazing crackles in their marbles.
They can also leave aside control groups that are not heated at all (and/or not placed into the water after being heated).
Each kid can record the data and evaluate their findings – all very scientific but also super fun!
We hope you’ve enjoyed this quick guide on how to make cracked marbles at home. If your kids like STEM activities, we think they’ll love this free printable activity book.
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