A Workshop for Creating Magical/ Fictional Crystals: A Guide from a Geologist
Hi folks, its me, here to talk about fictional writing again! Today I'm just tackling the idea of magical stones/mana stones by looking at existing minerals today and some neat properties that they have, and how you can apply these things to a fictional world. The goal is mainly to help you if you are stuck trying to come up with a unique magic system, or a unique identification/characteristic of your mineral.
First Things First: Mineral Shapes
I am exhausted, petered out, down-right fatigued by seeing every mineral depicted with having the crystal structure of calcite and quartz. There are soooooo many cooler, more interesting crystal structures, don't you think you would stop and take a look at a perfect cube in nature? It is completely unsettling.
Color within minerals can either be really important, or not important at all! It is your choice to decide if color is going to be something that means something to your mineral. But what are some times when the color is important? Well.... there are some elements that are called chromophores, this classification just indicates that these elements, when present, will determine the color of whatever they are in. So, if you wanted to treat mana like a chromophore, you could say, "Oh everything that contains mana turns green!" This could mean that regardless of the mineral, if that mineral is a specific color, it means it contains mana. This concept is exciting because you can just stop here and use minerals that already exist! You can also use it as an indicator for a magical ore! Chromophores are typically metals, so if you are making a new metal weapon, making the ore of that metal a unique color would make a lot of sense!
However, your mineral can also just be every color of the rainbow like quartz and perhaps that's what makes identifying your mana stones elusive and create an illusion of scarcity that your character can solve.
There are other things that can change the colors of minerals, like radiation damage, and electron exchange, but I think that is beyond what would be helpful! So lets talk about some unique color properties that happen in nature that seem magical in the first place! Maybe you don't need to design a mana stone, but you want a unique gemstone that only the royal family passes down or something (IDK).
The first one is the alexandrite effect! This is where a mineral can change color in natural light vs. incandescent light. (the mineral itself is not changing, but the lights contain different amounts of different colors that then get absorbed by the stone). Even if you don't use electricity in your fictional world, you could have the colors change in the presence of light magic. This could create fun misunderstandings about what the mineral is reacting to!
Pleochroism is something that most minerals have, it is frequently used to help identify minerals in thin sections, however minerals are usually not pleochroic enough for it to be visible to the naked eye! Pleochroism is just a fancy name to describe the change in how light is absorbed based on the angle of the mineral! So if you scroll up to the first image where I showed a lot of crystal shapes, most of them have angles where they are longer and shorter! This will effect the way light travels in the crystal. Tanzanite is a popular mineral that does this.
This is when a mineral will change color (in a reversible way) when exposed to UV light (or sunlight), I am not going to go too into the details of why this is happening because it would require me to read some research papers and I just don't feel like it. The mineral that is best known for this is Hackmanite!
Alright! These are all the really cool color effects that might inspire you or maybe not, but now I am going to talk about how you might find your minerals within a rock!
When I see a lot of magical caves/mines, typically I see them with some variation of a geode honestly, but most minerals are not found like that! Now I am sure most of you guys have seen a geode, so I will not really talk about those, but I will talk briefly about porphyroblasts which is when the mineral grows larger than the minerals around it, this happens in metamorphic minerals!
sorry random stranger, but this is an image of garnets inside a finer-grained rock at gore mountain in New York!
Another way you might find minerals is in a pegmatite! This is when all minerals are really large! This is a formed from really slow crystalizing magma!
But something else to think about is that your mineral might just be massive, it doesn't have to have distinct crystals, it may be similar to jadeite where small grains grow together which leaves it looking smooth and seamless! A note about all of these is that you would have to mine into the rock to find these, there would not be any natural caves in these rocks! Caves are only ever really formed in limestones and maybe marbles (rocks that react with acid).
How can your characters identify these minerals?
Typically when you are out in the field you will look to see what type of rocks the minerals are found in (The overall texture of the rock will tell you how it formed). If you know how the rock formed, it will narrow down the amount of minerals you need to think about by quite a bit! Next, you are going to look closely at it and observe its crystal structure, does it have an obvious crystal? if so what is the general shape? If it is broken, how did it break? Did it fracture like glass or did it break along uniform planes. Some minerals have a thing called cleavage (breaks along planes of weakness). If a mineral exhibits this habit, it will again help narrow this down. Next we can look at color. Color can be misleading, because minerals like quartz can be any color imaginable, but minerals like olivine will always be green! The next thing your character can do is test for hardness, minerals all have a specific hardness that can help identify it as well.
After you go through all of this, your mineral might have some special property! This could be magnetism, fluorescence, reactions to acid, or any of the color changing effects I mentioned above! Other than that, your character can take it back to a lab and do a number of things to identify it, but the most typical thing would be for them to make a thin section (very thin piece of the rock) and observe it under a cross polarized microscope!
On that note folks! I hope this helped in some way in thinking of new magic mineral properties! I have other guides that explore some different fictional worldbuilding issues you might run into, but if you have any topics you would like me to cover please that I haven't mentioned already, let me know!
