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This question might turn out to be more about physics then geology so apologies in advance if that is the case.

Years ago I read something that said in crystals "atoms have finite positions along the crystal lattice."

What I took that to mean was that in any crystal structure, atoms have a finite number of possible positions. Which is what I want to find out here.

After searching images for crystalline structures I found that all of them represent atoms as tiny balls that line up perfectly in a regular pattern.

enter image description here

What I take all this to mean is that, in a crystal structure, atoms can only exist in very specific places in accordance with their patterns like a cube made out of Lego bricks. They can only exist in, for want of a better word, a digital fashion. They always form straight edges and if another atom is added, it's like another Lego brick has been added to the cube, it can only be fitted in exactly according to its grid like structure. The atom can only be in column one row six or column three row four and so on. Like pixels on the screen.

enter image description here

My understanding is that, in a crystal lattice, atoms cannot take positions in an analogue way, they cannot be positioned in a lattice a few micro metres one way or the other.

What I conclude from this reasoning is that there is only a finite number of shapes that any crystalline material can take because of the digital nature of the positioning of the atoms, as opposed to the analogue way you can sculpt plasticine.

Is this so?

If we could shrink down to the atomic level and look at a crystalline solid with the entire structure look like a Lego sculpture or a pixelated image? Or do the atomic patterns allow for some degree of analogue placement?

I have read there is such a thing as screw dislocations.

enter image description here

Does this say that although crystal atoms do generally have a pattern, that pattern is not rigid and inflexible?

When you pour liquid glass into a spherical mould and let it cool or sculpt something out of clay and fire it, do the crystal lattices that form bend to accommodate these curved edges? Or is the solid still cubic in pattern and it just seems to be analogue because it's too small to be seen? Do screw defects only occur when someone or something is applied pressure to the crystal or do they naturally form with curved lattices?

And yes I'm aware crystal grains have non-latticed atoms between them and sometimes there is a missing atom in the lattice. But that's not what I'm talking about here.

To put it as simply as I can, to crystals onlay ever exist as lego scuptures or can the grow like trees with curved bows?

Edit: when I say crystals I mean crystals like what we call in every day life like pyrite and quartz, materials like stone and ceramics.

Thank you for your attention.

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  • $\begingroup$ You should have posted this on physics stack. Glass isn't a crystal, by the way, but quartz is. $\endgroup$ – Michael Walsby Oct 23 at 19:28
  • $\begingroup$ This question should really be simplified. As a mineralogist, I suspect I am the most qualified person here to answer your question. But, I don't understand what you are asking. $\endgroup$ – Gimelist Oct 25 at 10:07