you mentioned in the chat of a jello stream that you disliked how much fantasy magic crystals were shaped like Quartz. are there any specific crystal shapes you think are underutilized in fantasy?
I always like it when i see a nice beryl-or-andalusite-esque columnar crystal, or something botryoidal or acicular in a way that it makes little pom-pom shapes. And dogtooth (scalenohedral) crystals are a nice way to have that classic spiky shape without going quartz about it. But there's a whole entire world of weird and unique crystal shapes out there to base your fantasy crystals on, and I can't show off every possible shape that a crystal can come in with just one post. Pretty much every shape that a crystal can be is underutilized in comparison to the quartz shape.
the big thing that gets me about the "oops, all giant quartz clusters" method of designing fantasy crystals for your fictional world is that the shape a quartz crystal comes in, even though it's seen as like, the ubiquitous crystal shape that we think of all crystals as being, is actually very specific to quartzes!!!!
This is a figure from the mindat.org page on quartz. the top three shapes (a, b, and c) should be very familiar images to you! These are the most common shapes that crystals will be in fictional media. They're also three idealized crystal habits of QTZ - normal (prismatic), trigonal (prismatic), and pseudo-hexagonal (prismatic).
That's a lot of long words, but it all boils down to the describing geometry of a quartz crystal, and the geometry of its atomic structure.
QTZ is made of polymerized silicate, which, again, sounds fancy, but a polymer is just a long chain of many smaller molecules, and silicate is just the common term for the molecule SiO4. Silicate is a tetrahedron shaped molecule, meaning it's a pyramid with a square shaped base. A QTZ unit cell is made of a chain (a polymer) of silicate molecules linked together.
Here, we use unit cell to mean the simplest repeating building block in a larger pattern. like, say, if you build a giant lego cube out of all identical cube shaped legos, each cube shaped lego represents a unit cell of that giant cube. But QTZ unit cells aren't cube shaped. They're rhombohedrons- ie, 3d shapes where each face is a rhombus.
and if you stack a lot of rhombuses next to each other, they form a hexagon.
So when all the little unit cells of QTZ fit together, their ultimate shape is going to be hexagonal.
Quartz are not the only hexagonal mineral. Calcite famously also has a rhombus shaped unit cell. In mineralogy terms, this is called having trigonal symmetry- tri for three, as in the three rhombuses it takes to make a hexagon, or the three planes of symmetry a rhombus has.
But calcite doesn't form in in those tall prisms that terminate in pointy pyramid shapes made up of isosceles triangles or pentagons. It sometimes forms in dogtooth crystals, but dogtooth crystal faces are scalene, and they don't have that long prism body with a pyramid at the top like an endcap- they're spikes all the way to the base. Why is that? Why is quartz different from other trigonal minerals? why are its crystals weird like that?
Well, theres a lot of reasons, but one major one is that on top of being made of rhombohedrons, Quartz is ALSO made of helixes!
Thats right. Quartz has TWO fundamental patterns happening in its lattice. At the same time!
You can see by the overlayed yellow rhombohedrons in the figure above that each rhombus-y building block of QTZ fits together into a helix-shaped chain. QTZ forms in helixes because each of the basic silicate (SiO4) molecules in QTZ is sharing two of its oxygens with the other silicates its connected to. Because each block of the helix chain is made of a rhombus, when you stack those helix chains all next to each other to get a big quartz lattice, those chains make a hexagonal net. But helixes are also chiral, meaning they have a handedness to them- they can mirror each other and still be non-superimposable, like human hands.
To get the scope on why this chirality makes a difference to the structure of quartz, lets compare it to another mineral with trigonal symmetry, the aforementioned Calcite. If you could see atoms, this is what a chunk of calcite mineral would look like to you:
nice and simple, right? That's a very normal looking rhombus. everything slots together in a very straightforwardly rhombus-y way.
Now let's look at quartz.
ough.
When you combine these two features of QTZ geometry, the rhombus/trigonal symmetry and the helix shaped network of interlocking molecules, you get a pretty unique structure, which leads it to grow in very unique shapes when it gets bigger- hexagonal prisms with many interlocking chiral faces, terminating in those striking pyramid points composed of isosceles triangles.
That all sounds pretty cool right? it sounds like quartz is a really striking and unique and beautiful phenomenon of geometry, right? so why would I be annoyed? why would I be annoyed that a fantasy crystal has that unique shape? BECAUSE THAT SHAPE MEANS THE MINERAL IS QUARTZ.
Do you understand now? Out of all the possible permutations of different shapes a crystal can grow into, QUARTZ IS KIND OF THE ONLY FUCKING GUY THAT DOES THAT PARTICULAR SHAPE! nobody is out there doing it the way my guy quartz is doing it! So much so, in fact, THAT THIS IS THE ENTRY ON MINDAT FOR IDENTIFYING QUARTZ:
BY EYE.
QUARTZ IS ONE OF THE ONLY MINERALS YOU CAN ID BY EYE.
So, when you designed your mystical blue glowing crystal that has the power to harness a wizard's mana or whatever the fuck? And you picked that shape for it to be?
That means it's not enchantenite, or lunarite, or or whatever the fuck you want to call it. It's quartz. it's just quartz. your lack of creativity and unwillingness to do anything other than the most basic, recognizable shape for your fantasy crystal has all but guaranteed it. Maybe start worldbuilding what trace elements in that otherwise extremely fucking normal quartz you have there cause it to glow.
Because you picked the one shape that basically only quartz can be!
Congratulations!
enjoy your magical silicon dioxide, you piece of shit.
