How to Grow Great Crystals




Introduction: How to Grow Great Crystals

About: I enjoy making things by myself, trying to make this world better.

After a little research on, I didn't find an instructable which show you how to grow big and beautiful crystals. So I think that this instructable is a good idea.
Growing crystals is more than only a instructable, it is for me a passion, so a little piece of my soul was caught in them (in crystals).
For me, the word "crystal" means something like a DNA, because natural crystals have been created long time ago, and they have a piece of time history in them.
In this instructable you'll find how to grow several crystals and tips and tricks for growing them.
To grow a big wonderful crystal or a beautiful one, you may read all this instructable.

Step 1: A Little Introduction in the World of Crystals

What is a crystal ?
A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an ordered pattern extending in all three spatial dimensions. In addition to their microscopic structure, large crystals are usually identifiable by their macroscopic geometrical shape, consisting of flat faces with specific, characteristic orientations.(Wikipedia)

In this big world, are a lot of crystals and these crystals also have a lot of applications.
For example, your computer's processor is almost made from silicon, which is a crystal.
Or your keys, that are almost made from iron, which is a crystal too.
Or your wedding ring (if you're married), which I think it's made from gold, another crystal.

But crystals aren't all the same, they have a different structure and different properties.

Enough with talking. Let's start the work!!

Step 2: How to Make the Solution (slow Evaporation Method)

Needed materials:
- 100 g or more crystal powder (If you want to grow a big crystals, you should have more than 100 g)
- 100 ml distilled water (or boiled water)
- patience
- filter paper
- 2 clean jars

1. Mix the crystal powder and the water.
2. Stir until the powder stops dissolving.
3. Filter the obtained solution. Don't worry if the powder wasn't all dissolved. You should keep the powder remained on filter paper.
4. Let the solution for a while. A big crystal isn't growing a sudden.
5. Next time you'll take a look at your crystals, you'll see that there have grown many crystals there. Choose one that you like (a seed) and then put the remained crystals where you put the remained powder.
6. Filter again the solution and then put your little crystal in solution. (You may do that every time you'll see little crystals.)
7. When you see that in the jar isn't enough solution to cover the whole crystal, make some new solution as you have made the first one (I mean make the solution in a clean jar, filter it and then fill the jar that have you're crystal).
8. Growing crystals takes a lot of time, so be patient.

Tips(applied for all crystals):
  • You should cover your jar with something, maybe a filterpaper, because the solution can get some impurities from the air and then will grow many "parasitic" crystals
  •  If you want to quickly grow many little crystals, you can heat the water, but if you want to grow big nice crystals, you shouldn't do that.
  • Don't put your jar on a heat source.
  • Be careful not to break the crystal. (If you break it, you'll be really dissapointed, trust me.)
  • Don't taste the crystals.
  • If you have some small crystals sticked of your crystal, put your crystal in water and let it there until you don't see the small crystals.
  • If you want to quickly grow a little crystal, you can put a little "crumb" from powder as seed.

Step 3: Growing the Copper Sulphate Crystal

Needed materials for this crystal:
- 100 g Copper sulphate(CuSO4) and the other materials (water, filter paper ...)

These crystals are three months.

Warning!!: The copper sulphate is toxic, so don't taste it!!

Step 4: Growing the Aluminum Alum Crystal

Needed materials for this crystal:
- 100 g Alum(KAl(SO4)2) and the other materials (water, filter paper ...)

This crystal is three months.

This crystal isn't toxic, so you can taste it.
In the past, maybe now too, it was used to stop the bleeding.

Step 5: Growing the Potassium Dichromate Geode

Needed materials for this crystal:

- 200 g Potassium Dichromate(K2Cr2O7) and the other materials (water, filter paper ...)

For this "crystal", you can keep almost all the crystals deposited on the bottom of the jar.

After several days, you can hold the geodes in your hand.

These geodes are growing quickly and they needn't  so much care as the other crystals need.

Warning!!: The Potassium Dichromate is highly toxic, so don't TASTE it or TOUCH it without gloves!! DO NOT LET A KID PLAY WITH IT! DEPOSIT IT IN A WELL-VENTILATED AREA!

Step 6: Growing Nickel Sulphate Crystals

Needed materials for this crystal:
- 100 g Nickel Sulphate (NiSO4) and the other materials (water, filter paper ...)
Here you can obtain two types of nickel sulphate crystal, How you can do it ? It's simple. 
This crystals have a "special" property, if when you heat the solution up to 30° C, you get turquoise (turquoise is the color) crystals, and if the solution's temperature exceeds 30° C, you get translucent green crystals.

If you want, you can prepare the solution, and then you can add a little crystal as seed.

Warning!!: The nickel sulphate is toxic, so don't TASTE it or TOUCH it !!

Step 7: Growing Rochelle Salt Crystals

Needed materials for this crystal:
- 130 g Rochelle salt(Potassium sodium tartrate KNaC4H4O6) and the other materials (water, filter paper ...)
Tips: These crystals should be kept in a constant temperature environment.

These crystals have a special property, they are piezoelectric.
They produce electricity when you break one, when you yell at it ...
Don't think that they produce a lot of electricity!! You'll be dissapointed when you'll see how much electricity it produces.

Step 8: Growing Chrome Alum Crystals - Obtaining the Crystal's Solution and Growing the Crystal

How to obtain the solution:
I weighed 14.7 g K2Cr2O7 (0.05 moles) and mix it with 12.5 ml of 4 M H2SO4 concentration (0.05 mol)  and 100 ml of distilled water. We warmed slightly to obtain the solution. According to reaction's stoichiometry, we need 0.15 moles of SO2 can be obtained from 0.3 moles of Na2S2O3 (52 g) and 0.15 moles of H2SO4 (about 40ml).
Sodium thiosulphate was introduced in sulfur dioxide generator consists of an Erlenmeyer flask which was attached to a plug with a hole to put a separating funnel to add sulfuric acid in small portions. Heat gently to ensure a constant flow of gas.
For bubbling I used a rubber hose attached to a tube inserted in the second hole of the stopper. During the reaction solution I took care that the temperature does not exceed 40 ° C to avoid side reactions.

Tips: For cooling the solution during the bubbling, I used an ice bath.
During making the solution, don't exceed 60 °C because exceeding this temperature create complex chrome combinations.

Growing the crystals:
After obtaining the blue-green solution, you let it for a while. When you see many crystals grown on the bottom of the jar, choose one or two, and then dissolve the other.
You will obtain dark purple crystals.

This way to obtain Chrome Alum is thought by me because we haven't had Sodium metabisulfite as it was written in the originally recipe .

Warning!!: The chrome alum is toxic, so don't taste it!!

Here are the reactions:

K2Cr2O7+ H2SO4+3SO2 →K2SO4+Cr2(SO4)3+H2O
2Na2S2O3+H2SO4 →SO2+2S + 2Na2SO4 (sulfur dioxide generator)
K2SO4+Cr2(SO4)3+ 12H2O → 2KCr(SO4)2·12H2O

Step 9: Mixing the Aluminum Alum and Chromium Alum Solution to Obtain a New Crystal

Because both Aluminum and Chromium have almost the same formula and structure, you can mix them together and get a new nice crystal.
For obtaining the new crystal, you have two ways:
  1. Mix a part of Aluminum Alum solution with a part Chromium solution. You'll get light purple crystals.
  2. Mix the two solution together and then add a Aluminum Alum crystal as seed. You'll get a two colors crystal - inside, it is clear, and outside, purple. 

Step 10: Obtainin a "Gold Rain"

Procedure: In a beaker mix 25 ml 0.2 M solution of Pb(NO3)2 and 0.25 ml of KI with 0.4M concentration.  Observe the formation of an abundant amorphous precipitate of lead iodide. Then let it decant and add hot distilled water in a ratio of 1:4 to the yellow suspension  initially obtained, then heat to dissolve the precipitate. If it doesn't completely dissolve, distilled water is added and continue heating. By slow cooling, we observe the formation of small "flaps" of gold that are actually lead iodide. By rapid cooling, is observed a large number of crystallization centers that give the appearance of yellow-pearl.
The reaction is:
Pb(NO3) 2 +2KI → PbI2 + 2KNO3.


Step 11: Obtain "Stars" in Gelatin

To obtain single crystals of magnesium hydroxide I used slow diffusion of reactants technique in a gel. For this purpose I mix 8g gelatin gel with 200 ml of distilled water to prepare the gel environment. I added 2 ml of 10% solution of MgCl2 and I shake it for homogenization. I introduced the gelatine in a graduated cylinder and waited to strengthen. Meanwhile I prepared 5 ml of concentrated ammonia solution 5M that I added over gelatin. Crystallization process is very slow. In the early days there were few white rings of precipitate formed (Liesegang's rings). After two weeks have been shaped crystals of magnesium hydroxide.
The reaction:
MgCl2+ 2NH4OH → Mg(OH)2 + 2NH4Cl

Step 12: What Can You Do With Them ??

I'm thinking about a lot of applications.
When you're sure that you don't want to grow them bigger, just spray them with some varnish.
One of them is that you can make handmade jewelry like earrings, rings or pendants. (ONLY WITH NONTOXIC CRYSTALS)
You can use them to show your friends how great is chemistry.
Stay tuned. I will show you how to make some jewelries with them.

Step 13: And That's It!

I hope you liked my crystals.
By the way, sorry for my bad english.
And a little video for you. You can see how the silver is growing on the copper wire. Enjoy!

Step 14: For Make-to-Learn Youth Contest

What did I make ?

I grow some crystal to show people how great are them and how great is chemistry. First time I was in the chemistry lab I wanted to grow some crystals. They aren't just nice, they can be useful too.

How did I make it ?

I just got what I was needing, I made the solution, let it dry, and then grow more crystals. I know that it looks easy to grow, but it isn't.

Where did you make it ?

I have made them at school, in the chemistry lab, but you can also DIY them at home.

What did I learn ?

I learn that if you put a piece from your soul in your projects, it can become something great. To make something nice, you must like it, you should work hard and you may be patient. Great thing haven't appeared in one night. I saw a lot of great things made using crystals.

Make-to-Learn Youth Contest

Fourth Prize in the
Make-to-Learn Youth Contest

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Participated in the
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    Question 6 months ago on Step 3

    What is the hardness of lad grown crystal?


    2 years ago

    I came across this beautiful, small chandelier that has been covered in small crystals. I wonder if you have an idea about what kind of crystals were used in creating it.
    I'm hardly a chemist but I've wondered if it was created using simple alum crystals, which were then "hardened" by spraying them with an epoxy or resin. Obviously, the crystals would need to be fairly durable since they would be handled and installed--likely exposing them to being accidentally hit against a hard object.
    I've watched your videos above and think that you might have a clue.


    Reply 2 years ago

    It looks like it's made of something stronger than Alum, like quartz.
    You can try using epoxy, but you have to be careful about the layer, as the thicker it is, the least you are going to see the crystals. And the layer needs to be quite strong to keep the crystals together.
    You could also try with some strong transparent glue sprayed on the crystals to keep them together.
    One thing good to know is that the smaller the crystals are, the trickier it is to stick them together.
    I advice you to experiment with it, and why not, even write an instructables article.


    Question 2 years ago

    On Step 9, I just want to verify the compounds that we're looking for.
    Potassium Sulphate (not Aluminum Alum?) as KAl(SO4)2
    and Chromium as K2Cr2O7

    Thanks. Totally know-nothing non-chemist just trying to figure out what to shop for.


    Answer 2 years ago

    Hi hhazel. The names of the chemicals you need to make the purplish crystals are Potassium alum with formula KAl(SO4)2 and Chrome alum with formula KCr(SO4)2. Both of them can crystalize (become crystals when the water evaporates in this scenario) without being mixed together, but one is transparent and one is dark purple alone.


    Reply 2 years ago

    amazing, thanks so so much!


    Question 3 years ago on Step 5

    How dangerous is Potassium Dichromate, and what disposal precautions should you take?


    Question 4 years ago on Introduction

    Where do you get the chemicals for making these crystals? I've played around with common household ones (Borax, Alum), but they tend to be a bit boring. Also have you ever tried using a pressure cooker to change conditions?


    Answer 4 years ago

    Hi Kevin. I had those chemicals from the chemistry lab. I didn't procure them myself, but you can usually buy them from Amazon or any other e-shop that sells chemicals. I don't see alum as boring, but it depends what you are trying to achieve.

    If you are trying to get a nice perfect crystal, you need a lot of time and patience.
    But anyway, I believe that it is quite easy to get copper sulfate, as it is used, or was used in agriculture.
    I don't know about pressure cooker conditions, but I think it might not be indicated, if you are trying to get a nice big crystal, as it makes the water boil and then you might not actually get any seed, because the environment will be very agitated and warm.

    You need a cool dry environment to get the water soluble crystal to form.
    It is true that the crystals that grow in the ground are created under pressure, but the mixture containing the crystalline substance has quite a high temperature before it cools. And I wouldn't compare the pressure underground with the pressure of a slow cooker.

    But all I can say is that you can try and experiment with different conditions.
    So good luck!

    Dimitrios Karampistis

    I am growing potassium nitrate crystals, I chose one and I am making it bigger and bigger, how can I make it stronger? I mean if it falls it will break... How can I make it more durable?


    Reply 4 years ago

    I don't know that you can make the crystal structure itself stronger. What I would do is grow it to the size you like and encase it in an epoxy like you would to preserve a flower. That'll last through a nuclear war.


    5 years ago

    Thanks for this instruction. I've been experimenting for a couple weeks now. When you mention that heating the water will not make large crystals, can you dissolve Alum in cold water? Or should you boil water, dissolve it, cool it, then start the crystal process? I'm encrusting little sculptures.
    Thanks again!


    100% COOL . . .

    ; D


    Do you have any experience with growing durable clear crystals? It looks like Alum crystals are simple to grow, but aren't very strong and break easily? I'm doing an art project but need strong, durable clear crystals. Any help would be greatly greatly appreciated. Thanks!


    Reply 5 years ago

    Hi there. Yeah, I have some experience with growing crystals, but growing a durable one means a lot of time. There a currently multiple way you can use in order to grow a nice big crystal, but don't expect hand-size crystals. Also, growing a clear crystal means maintaining its structure while keeping it away from any other crystal. It is like growing flowers. In a garden, weeds appear too. So you will have to remove the weeds (other crystal seeds that might attach to your big crystal).
    For some crystals, which have growing time big when compared to others, it is quite easy to maintain this structure, but other crystals, like copper sulfate are hard to maintain, as they grow pretty fast.
    You can apply a varnish layer in order to maintain crystal look, but durability is not a feature of the growable crystals.
    Only nature (and devices) can provide durability using specific conditions like high atmospheric pressure or high temperatures.

    Skeleton King
    Skeleton King

    5 years ago

    How long does this take?


    Reply 5 years ago

    If you are referring to growing a crystal, then it takes how big you want your crystal to grow. A big nice crystal can take months to grow.


    6 years ago

    Very neat instructable, I wonder if I can grow crystals that will give me +2 Strength, +3 Dexterity, +2 Intelligence +3 Mana :)

    Anyways, when I was a kid I have found a stone in nearby mountains, inside it is a colorless crystal, like the whole stone, I wonder what it is. I'll try to find one and post it here.

    Also, my friend found an obsidian crystal, I wonder how it is worth.


    Reply 5 years ago

    Obsidian is a natural glass produced through volcanic activity. It is not a crystal. While it is used to make jewelry, obsidian is not particularly valuable, though it does look pretty cool.


    Reply 5 years ago

    Yeah they do look cool (especial) when they're shinny you may want to consider a shiner to make it look better (depending on how it looks)

    P.S I think lacquer may work but i'm not sure