Here’s how you can transform regular table salt into gorgeous pyramid salt crystals at home.
Regular salt looks like a fine white powder. Sure, it tastes good, but it’s not very interesting to look at.
But what if I told you that you could transform the salt sitting in your kitchen into a work of art?
What if I told you that within a few hours, you could turn white, powdery salt into premium salt crystals shaped like pyramids, flowers and Eiffel towers?
Plus, you don’t need to be good at art. You don’t need to carve those pyramids yourself. Just sit beside the stove, and watch as pyramid salt crystals grow from a dish of salt water right before your eyes.
Let me show you how to do just that.
To my knowledge, it’s the only such guide on the Internet.
First, let’s answer a question.
What is pyramid salt?
Pyramid salt crystals are made of the same stuff as regular salt. But these crystals look different because they formed in a different way.
In nature, these elusive crystals grow on the surface of quiet, undisturbed pools of salt water that evaporate under the hot sun.
Pyramid salt is more expensive than regular salt, because they taste saltier. Pyramid salt is hollow, and gram for gram, it dissolves in your mouth faster than regular salt. So the saltiness comes at your taste buds all at once.
Plus, they also look awesome.
Now, it’s easy to make regular salt crystals at home. Just leave a dish of salt water to evaporate, and you’ll get white powdery salt inside after a few hours.
However, it’s much harder to make pyramid salt.
True, you can buy them online. Maldon Sea Salt, for instance, contains crunchy pyramidal salt crystals. They are made by evaporating sea water in large heated pans, mimicking nature.
But that kind of salt is produced industrially, with special equipment and mineral rich seawater.
I’ve always wondered whether you could grow pyramids at home using a hot plate, a glass dish and some regular table salt.
It took over 100 experiments and some sleepless nights, but here are the results.
How to make pyramid salt crystals
This guide will consist of the following parts:
- Preparing the salt solution
- Growing the pyramid salt crystals
- Harvesting the pyramid salt crystals
- Storing the pyramid salt crystals
- Tasting the pyramid salt crystals
- 8 types of pyramid salt crystals
- Some more information
To make pyramid salt crystals, you’ll need:
- A bag of salt
- Alum powder
- A stove/hot plate
- A heat resistant glass dish
- A pair of tweezers
- A thermometer (optional)
I have tried table salt, sea salt, and Himalayan rock salt, and they all work. Sea salt seems to give better results.
I’ve used both tap and deionized water. Both are fine.
Also, in this experiment, we’ll be heating some very concentrated salt water. This solution will damage metallic objects, so you can’t use a stainless steel pot.
Instead, I suggest using a heat resistant glass dish. The exact type doesn’t matter. You can use a Pyrex dish or an enameled cast iron pot, which won’t get corroded.
I used a glass casserole.
Preparing the salt solution
Dissolve 165 g of salt in 500 mL of hot water. If you want to make a bigger batch, just use the same ratio (e.g. 330 g of salt per 1 L of water).
Stir the solution gently until all of it dissolves.
Depending on whether the salt is dirty, you can choose to filter it. I filtered mine.
In my setup, I poured my filtered salt solution into a glass casserole sitting on top of a hot plate.
A hot plate is fine. But don’t put the glass dish directly on the gas stove – the glass might break due to strong, uneven heating, even though it is technically heat resistant. Use a water bath instead.
Growing the pyramid salt crystals
Now, heat the solution to 60-70°C and keep it there throughout the growing process.
When the solution warms up, convection currents start forming, causing the surface of the solution to swirl around.
This is bad news, because when our pyramids form, they will also move around the surface of the solution. And they will bump into each other, stick together and fall to the bottom of the dish.
The key is to add an ingredient called potassium alum. Alum calms the surface and helps the pyramids form. It is normally used in baking and pickling. You can find it at the grocery store, or buy it online.
Add 0.5 g of alum per 500 mL of salt solution. No need to measure – just drop a few pea-sized pieces of alum/two pinches of alum powder into the solution and let it dissolve.
Several minutes after the alum has dissolved, the surface of the solution should start to settle down. Check out this GIF:
I placed a cork on the surface of the solution to visualize the movement on the surface. Before adding alum, the cork swirled around. After adding alum, the cork was completely motionless.
Good. Now you just need to wait.
It takes about 30 minutes for the salt solution to reach saturation, which is the point where salt crystals start to form.
Eventually, small white squares will appear on the surface of the solution.
Those are baby pyramid salt crystals.
They’ll keep growing, and within 15 minutes they’ll look like this:
The crystals are actually upside down pyramids, suspended on the surface of the solution due to surface tension. It’s the same principle that lets some insects walk on water.
Here’s what they look like from the side:
As the pyramid salt crystals get heavier, they sink lower into the solution. But evaporation on the surface causes the base of the pyramids to grow outwards, widening it and forming a staircase pattern in the process.
Here’s a time lapse of the growing process over 1 hour:
As the pyramids get larger, they risk bumping into their neighbors.
Usually, it isn’t a big problem – unless your solution is too hot. If you heat it beyond 80°C, the pyramids quickly join together to form a layer of crust.
But even at 60°C, you shouldn’t leave them there, because they might get too heavy and fall to the bottom to the dish.
So it’s time to harvest the pyramids.
Harvesting the pyramid salt crystals
Using a pair of tweezers, carefully remove the pyramid that you want, and place it on a piece of tissue paper. The paper will soak up excess salt solution.
Before you remove the second pyramid, dip the tweezers in a cup of water. This step ensures that there are no powdery salt grains sticking to your tweezers – which will cause thousands of tiny crystals to form in the dish.
Then, dry the tweezers with a tissue, and remove your second pyramid. Rinse and repeat.
Instead of using tweezers, you can also use a sieve to scoop up those pyramids. Remember to dip the sieve in water after every run.
Wash your tweezers after every run to prevent powdery salt grains from forming.
You can keep doing this until the salt water starts to dry out. By this time, you should have quite a few pyramids.
And that’s it!
You’ve just made the fabled pyramid salt, also known as fleur de sel, flower of salt, at home.
If you want to make more pyramids, just add some water to the dish and wait for all the salt to re-dissolve. Then repeat the process. This time, you don’t need to add alum.
Re-dissolving the salt to make more pyramids.
Storing the pyramid salt crystals
Just store them like regular salt.
If you live somewhere humid, the crystals will absorb moisture from the air and get slightly wet. This will cause part of the pyramid’s base to dissolve.
It’s no big deal, but if you want to prevent this, store the pyramid salt crystals with a desiccant.
Tasting the pyramid salt crystals
What do you mean?
Of course I’ve licked the pyramids.
They taste a bit saltier than regular salt. And crunchier.
You might also wonder if the alum added to the solution changes the taste of the salt, or if it’s unhealthy.
First, we added an extremely small amount of alum to the salt solution. So the pyramids taste like pure salt.
And since potassium alum is used in baking powder and considered safe by the FDA, it’s alright to bite a pyramid or two.
However, I would discourage you from eating pyramid salt grown with this method regularly. I’m no dietician, and it’s best to look for an expert before adding something new to your diet.
8 types of pyramid salt crystals
At the start, I promised you’d see all sorts of pyramid salt crystals, some narrow, others wide. I told tales of Mayan pyramids, flowers and Eiffel Towers.
Below you will find pictures of 8 different types of pyramid salt crystals and how I grew them.
1. Regular pyramids
Regular pyramids are the most common type of salt crystal. They form from a solution heated to 60-70°C at low to medium humidity.
They look like the typical right pyramid, with a square base, and straight edges that meet at the top. The edges have small crystals on them.
Remember, pyramids form upside down – hence, they grow from the top to the bottom. Since salt crystals get larger the longer they stay in the solution, the crystals near the top are bigger than the ones at the bottom.
2. Thick pyramids
Now, regular pyramids are thin and fragile. But if they drop into the solution and are left there, more crystals will deposit on their surface, thickening the faces of the pyramid.
Compare the regular pyramid, grown on the surface of the solution, vs the pyramid that fell to the bottom of the dish and left to thicken as more crystals formed on its surface.
These “thick” pyramids might look less elegant, but they are also less fragile.
3. Two sided pyramids
Once, I tried to pick up a pyramid with my tweezers, but by accident, it fell back into the solution. Instead of sinking, it continued to float – but with the tip of the pyramid facing up, and the base facing down.
I let it grow for another 15 minutes, and the pyramid turned into this magnificent hourglass shaped crystal:
4. Narrow pyramids
Pyramid growth is a balancing act between gravity and how fast the base of the pyramid can widen. Sometimes, the base of the pyramid grows very slowly, while gravity keeps pulling it downwards.
As a result, we get narrow salt crystals that look less like pyramids and more like Eiffel towers, or chess pieces, if you will.
Salty chess. When you capture a piece, you eat it.
These narrow pyramids like to form when the temperature of the solution is below 60°C.
My theory is that when the temperature is low, less evaporation occurs, and so less crystal growth occurs at the surface. Thus, the pyramids sink faster than they widen – hence the narrower shape.
If you increase the temperature while these salt crystals are forming, the base will get wider, curving outwards. The resulting pyramids look like trumpets.
5. Big headed pyramids
If you look closely at the pyramids, you’ll find that each pyramid has a “head” at its tip. Sometimes the head is small, sometimes it is big.
Below are some big headed pyramids.
The so-called “head” is actually a large salt cube. When it starts forming, it looks like a tiny square on the surface of the solution.
Then, as the crystal gets heavier, it sinks a little into the solution. As it sinks, layers of salt crystals grow on the face of the cube facing the sky, forming a pyramid. But the other sides of the crystal cube (that are underwater) also keep growing. Eventually, they form the “head” of the pyramid.
Sometimes, the head is tiny. Sometimes the head is much larger, and you can see interesting patterns on the hopper crystal.
If you place the pyramids upside down, they look remarkably like flowers. You might be able to serve some ketchup in them.
Despite having spent an unhealthy amount of time on this project at home, I confess that there was one secret that escaped me: how to control the size of the heads.
At first, I thought it was due to different types of salt. So I tried comparing two types of salt – sea salt and rock salt. I found that the batch with sea salt gave big heads and rock salt gave small heads.
I thought I had my answer.
After a few days, out of curiosity, I ran the two experiments again, side by side. This time, it was the opposite – sea salt gave small heads and rock salt gave big heads.
I was equal parts surprised and confused.
And we haven’t even gotten to the scary part yet.
After 15 minutes, the heads on the sea salt pyramids started growing bigger, until they were just as big as the heads of the rock salt pyramids!
Such was my hunt for the reason behind different head sizes. I tried changing the temperature and the type of container. I tried using deionized water. I even tried adding impurities such as vinegar and baking soda to the solution.
But my efforts were mostly frustrating and fruitless. It was full of contradictions. I was as salty as the saturated salt solution and my mood as sour as the vinegar I added to it.
Top and side view of big headed pyramid salt crystals.
My last hope was the effect of humidity. But I didn’t have a device to measure humidity. So I had to rely on a crude technique – obsessively checking the weather station reports. Based on the several experiments I did, there seemed to be some relationship:
The lower the humidity, the smaller the pyramid head.
My tests were not conclusive, as occasionally large heads still formed on hot sunny days. But generally, drier days yielded smaller heads.
I’ll discuss this later. For now, let’s look at 3 other types of pyramids.
They were grown from the exact same salt solution – in which I had added a teaspoon of Epsom salt.
6. Monster pyramids
The first pyramid salt crystal that grew from this solution was an absolute beast. The humongous head was covered with all sorts of intricate formations that reminded me of bismuth crystals.
After half an hour, I extracted this crystal with tweezers and dried it. Then, from the same solution, a different type of pyramid started forming:
7. Slanted pyramids
At first, it looked like a regular, small-headed pyramid. Then, it tilted over to one side and continued growing, until it looked like this:
8. Ultra wide pyramids
After removing the slanted crystal, more pyramids continued to form. These were regular symmetrical pyramids with small heads. But they were also very flat – the flattest I have ever seen:
3 different types of salt crystals forming from the same solution, barely an hour apart.
I was reminded once again that the art of crystal growing is both mysterious and wonderful.
Some more information
Before writing this article, I have looked online for guides on how to grow pyramidal salt at home, and found nothing.
But I did find a study published in the World Salt Symposium where researchers successfully grew pyramid salt from waste salt water in large, steel crystallizers.
They claim that calcium ions in seawater help pyramids form by allowing more salt to dissolve in water. I tried adding various amounts of calcium chloride to my solutions, and it had no noticeable effect.
They also claim that a pH of 4, and a temperature of 55-65°C was good for pyramid growth. My experiments agree.
Since alum is mildly acidic, dissolving some alum in water would indeed yield a pH of around 4. But I have tried using other acids like vinegar and cream of tartar. Neither yielded pyramids. I suspect it has something to do with aluminum ions, because replacing potassium alum with aluminum sulfate worked.
Finally, according to the authors, sulfate ions were bad for pyramid growth because they encouraged hopper cubes (we know them as “heads”) to form. After removing the sulfates, the researchers managed to grow nice regular pyramids.
I knew that sulfates were not the only factor that affects head size, because in my experiments, the same solution could form both big and small heads.
Nevertheless, I decided to try this hypothesis. I had no easy way to remove the sulfates, but I could add Epsom salt (magnesium sulfate) to my solutions.
You have seen the results in the previous section. The same solution formed monster pyramids, slanted pyramids and ultra wide pyramids, 1 hour apart. Maybe magnesium sulfate indeed makes the heads bigger, but then, it must be quickly used up, causing subsequent pyramids to have very small heads. But it’s hardly conclusive.
What do you think?
How do you control head size? Whether you’re a science loving kid or a research chemist, I leave it to you.
That’s all for now. I have been trying to grow pyramid salt crystals for a very long time, and I’m glad to share what I’ve learnt with you. Hopefully you found the guide useful.
Here’s a super short summary of what we’ve covered.
To grow pyramid salt crystals, you’ll need:
- A bag of salt
- Alum powder
- A stove/hot plate
- A heat resistant glass dish
- A pair of tweezers
- A thermometer (optional)
- Dissolve 165 g salt per 500 mL of water.
- Heat the solution to 60°C.
- Add 0.5 g alum per 500 mL of solution.
- Wait for pyramids to form.
- Remove the pyramids with tweezers.
- Dry and store them with a desiccant.
- Enjoy your pyramid salt.
Thank you for reading.
Maybe you found a new hobby today. Maybe you’ll find a few hours of joy with your kids. Or maybe it simply put a small smile on your face.
I grow crystals because it makes me happy, and I hope it made you happy too.
If you want to start crystal growing, I also recommend making alum crystals. They are large, transparent and easy to grow.
And if you enjoyed this guide, consider subscribing to my newsletter. Let’s keep in touch. I’ll share more crystal growing guides with you when they come out.
As always, happy growing.
Are all salts work for making Pyramids. I have tried a lot with different rock salts as we have a lot in our country,Pakistan. But these rock salts did’t worked as you mentioned. What is the reason behind this.?
I have tried rock salt before, and it worked for me. But different types of rock salts have different mineral contents. Can you tell me more about how it did not work? What did you observe?
Hello! Awesome article. I was wondering if you knew a way to keep the pyramids normal when they’re on the bottom for a long time? I wanted to make some but would want to make a big batch and just forget about it (lol). Is there a way to let the crystals sit on the bottom of solution without getting bulky? I can’t imagine big business that sell flake salt take them out before they hit the bottom. Thanks for the reply
I don’t know of any such method. Businesses do indeed harvest their flaky salt by scooping them up from the surface and selling them as high quality flaky salt, while selling those at the bottom as regular salt.
Cora A. Harris
Chase, these pyramid salt crystals you’ve grown are absolutely amazing! Just signed up for your newsletter too. Thanks for posting awesome stuff like this! – Cora
Hey Cora, super happy you liked it! Your work is awesome too.
Hello from Kenya!
I was wondering about your thoughts about using a heat-proof glass dish in the oven set to 65 degrees – would it be too dry? I thought perhaps a second dish of water on another shelf might help with the humidity. And do you think it makes a difference adding the alum before or after filtering?
Thank you for your detailed and fun write up!
I think it should be alright. Water will evaporate inside the oven anyway. When you add alum isn’t too important, but if the alum makes the solution cloudy because it is impure, then add it before filtering so that you can filter out the cloudiness. Good luck!
You posted an optimal temperature range of 55-65 , but how important is it to be held at a temp or can it fluctuate? I have a steady hold temp at 50 (which I found was too low and the cystals were smaller, but with my plate cycling with bursts of heat but managing to get my temp closer to 65-70c I had bigger flakes but they sank a bit faster and i ran into harvest issues missing windows lol….
The crystals grow too slowly below 50C, and they also appear narrower. The crystals are much wider and grow more chaotically at temperatures above 70C, to the point where they sometimes join into crust. 55-65C is not a hard rule, but generally I found it to be the right balance between those two conditions to get the best pyramid salt crystals.
Thanks for the reply! Would cycling temperature swings from 62-70 every 2-3 minutes make the pyramid structure so that they sink faster? I’m just not sure how much extra effort I should put into holding the temperature steady
It should be fine. I’ve noticed no significant effect when the temperature fluctuates slightly. If you really want to keep the temperature stable, you can place the salt solution in a water bath and heat the water bath instead. Good luck!
Thanks – interesting and well-written as always.
Do you think it’s possible to grow a crystal with some sort of inclusion in a home setup (e.g. https://www.geologyin.com/2017/01/types-of-mineral-inclusions-with-photos.html)? Say, for these, could a higher-density liquid be dropped into the pyramid once it’s a decent size so it pools at the tip?
Where did you find this trick of stabilizing the liquid surface by adding alum? It looks very susseful!
I got the idea of adding alum after seeing that the research paper (mentioned in the article) successfully produced pyramids from salt solution containing several different types of ions, including aluminum. They didn’t mention that aluminum ions were beneficial in particular, but since I had some alum on hand, I decided to give it a try, and it worked!
This is so cool! Inspiring how much time and effort went into this. I need to master this so I can be a wizard dad when I have kids.
I really enjoyed reading this! You have a an engaging writing style that maintained my interest throughout the article. I really like how you asked questions and encouraged your readers to engage and learn.
Yay! I tried my best to make the article both interesting and informative. Glad you liked it.
Thank you for making this detailed and funny guide. I will share this with my students. Last school year we grew some crystals from store bought kit and they love it so much.
wow, this was extremely interesting!) Thank you!!!
Thank you for the article!!! Great piece and the pictures you added are so helpful. This was really a fun read.
Please reach out to Adam Ragusea! He had a great video on salt crystals and his own attempts at growing hopper crystals. I’m sure he’d be delighted to learn about your findings!
I’ve watched the video before! I will! Thanks for the suggestion.
I had the exact same thought.
Thanks so much for taking time to write this up. I will be growing some pyramids with my 7 year old son who loves science.
Best regards, Teun (from the Netherlands).
You’re welcome. Spend some quality time with your son, and all the best!