One of the most common chemicals you can grow crystals with is table salt.
You might have heard that although salt is very common, growing crystals with it is hard.
Yes, and no. Growing big, transparent salt crystals is indeed very difficult, but anyone can easily grow a beautiful cluster at home.
Preparing the solution
First, prepare half a cup of salt (around 150 grams). Make sure you’re using regular table salt and not iodized salt, because it will mess up the crystal growth.
Next, pour 400 ml of water into a pot and heat. When the water is close to boiling, turn off the heat and add the salt. Then, stir the solution quickly for several minutes to try and get as much salt to dissolve as possible.
After 5 minutes, most of the salt should have dissolved. If there’s a little left at the bottom, it’s fine. Wait for the solution to cool to room temperature. After that, pour the solution of concentrated salt water into a transparent cup without including the undissolved salt.
Congratulations! You have finished preparing the solution to grow crystals with.
Preparing the seed
Now, all we need is a seed crystal to kickstart the growth.
A seed crystal is a tiny crystal that we will hang inside the saturated salt solution. We can get a seed crystal using one of two methods:
Look inside your jar of salt. Are there any chunks of salt that are hard, and do not fall apart when you hold them? Ideally they should be 0.5 to 1 cm long.
If so, pick them out, and jump to the next part by clicking here.
If your jar of salt is too fine and you can’t find any chunks, that’s fine. Remember the cup of saturated salt solution you just prepared? Now leave it under the sun for a day.
If you have cloudy or rainy weather instead, you can also leave it indoors for 2-3 days.
After a few days have passed, a layer of tiny salt crystals should have formed at the bottom of your cup. Now, pour the salt solution into another cup, while leaving the salt crystals/crust at the bottom of the first cup.
Break up the crust with your fingers into small pieces. Choose a piece that looks good and is about 1 cm long. That will be your seed crystal.
Tying the seed crystal
Tie the middle of the seed crystal to a string or fishing line like this:
Tie the other end of the string to a stick/pencil. Then, lower the suspended seed crystal into the cup containing the salt solution. Leave the cup at a cool, dry and undisturbed place. A storeroom, cupboard or basement would do just fine.
The solution will slowly evaporate, and the salt dissolved in the water will attach itself onto the seed crystal, making the crystal faces grow larger.
The process is quite slow, so to get large crystals, you might need to wait a month or so.
Here is what it looks like after a day:
After a week:
After a few months:
The crystal cluster will steadily get bigger the longer it is in solution. When you decide it is big enough or when the water level starts to become too low, you can take it out of solution.
Drying the crystal
After 6 months, I decided to stop the growing process. How long you grow yours is entirely up to you.
Dry the salt crystals by placing it on a piece of tissue paper. Then, having absorbed most of the salt solution, put it on a flat surface to air dry.
It is important to dry the crystal because if this step is not done properly, the remaining salt solution on the surface of the crystal will evaporate and form flaky crust on the pretty crystal faces.
And you’re done!
Take a moment to admire its beauty, and display it any way you like.
Crystals made of some chemicals turn powdery over time, but salt crystals have no such problem. Just keep it away from water to prevent it from dissolving.
If you’re an expert crystal grower and you want a challenge, check out how you can grow perfectly transparent salt cubes here!
Enjoyed the read? Have any questions? Share them with me in the comments below!
Thank you for reading, and as always, happy growing.