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How would I grow a giant crystal formation? Answered

I have a 3 foot height by 1.5 foot width rectangular container of which i intend to grow a crystal formation in.  Does any one know how?
That wont be toxic and wont dissolve?


hmm well specifically I was thinking to grow a seed crystal by boiling water and then saturating it with the chemical I wanted to crystalize next I would create an armature of the shape i wanted then I would cover it in a plaster and before it sets I would put the seed crystals in the plaster I would put this armature in a large mold thats negative space resembles a slightly bigger version of the armature's shape so the crystal would not overgrow in certain places then I would pour a heated water saturated with the chemical into the mold and let it sit until the crystal filled out its shape I am thinking to use Alum

Well... There are ways to get _some_ shapes as crystals other than the ones which form naturally. The semiconductor wafers from which most ICs are made are polished slices of a rod/ingot which is grown with a nicely regular crystalline lattice, by pulling it at very carefully controlled speed from an ultra-pure melt with as little vibration as possible. (Or at least, that used to be the standard approach; may have changed by now.) But if you want a molded "crystal", I still think polymer resin or glass would be better choices. What are you actually trying to accomplish?

all great information thank you but let say i had a mold is there a way to grow crystals in the mold's shape?

Does it have to be a crystal? Sounds like a plastic resin would be a better choice if you want to mold it.

The shape of the crystal is governed by the atomic structure so changing the shape of a pure crystal as it grows would be difficult - I think.

Molecular beam epitaxy, or using an AFM, would let you do it :-)

No. It wouldn't be a crystal. You can make an amorphous solid in a mold.

Mix your chosen salt with water - Sugar and Salt are a good starter.

Dissolve as much of the material in the water as you can - This normally requires hot water. Take normal care with hot things

Pour off the liquid leaving any undissolved behind, the liquid is a super saturated solution and MUST be free of any solid matter or it will crystallise in a random way.

Find a good example of a crystal of the material you used and tie a cotton thread round it and hang it in the solution - a pencil makes a good hanger across the top of the glass.

Put the glass somewhere where it won't be disturbed and watch your crystal grow. Occasionally take the growing crystal out and brush off any small crystals that may form to keep the shape pure.

It takes weeks!

That's the secret - weeks, no disturbances, and very uniform temperatures. If you've got a basement, put it down there.

Failing that find some water glass and some examples of metal salts. There are numerous web pages to describe how to do this if you search.

it takes time to grow big crystals, but you can do it with sugar.