Xhin
While everything is subject to change, items are relatively stable so I'm going to describe how some of the different magical items work.
Crystals
Crystals, also known as Spelljewels, are the foundation of personal magic. Without getting too much into how mana in general works, they're basically concentrations of
mana currents -- crystallized material forms of nonmaterial forces. While energy can be turned into matter relatively easily, having this happen naturally is pretty rare and involves some really unlikely scenarios.
In any case, having access to concentrated mana currents allows a mage to shape their own personal mana into various effects.
Scrolls
Crystals can be smashed into a kind of powder -- while this makes the currents dissipate over time, it allows the crystals to tap into
World Mana instead of personal mana. Highly useful if your own mana is weak or a spell is just too far out of league.
Scrolls are created by mixing crystal powder with ink, and then using a quill to set it to paper. The most effective scrolls are those that use symbols linked with the element in question -- triangles for ice, circles for water, crosses for wind, spirals for fire, rectangles for earth, stars and other complex shapes for wood.
To use a scroll, it must be ignited. The best way to do this is to just concentrate your own mana in a spiralling helix on it. This uses so little mana that it's replenished pretty much instantly. If you have a torch, you could just drop it on there or w/e.
Wands
Wands are created by fusing crystal powder with carved sticks, in a process known as the Wanding Ritual. Essentially, various patterns are cut into a still-green stick -- notches, grooves, spirals, etc. The stick is then rotated while crystal powder is poured on it. This process repeats until all of the crystal powder has stuck to the stick. It's then dried, either manually or by fire, and it turns into a Wand.
Like scrolls, there are different types of stick carvings that improve different kinds of spells, though these are minor differences compared to the material of the stick, which makes a huge difference.
Wands are used in a fast motion that rotates them while roughly slashing them in a certain direction. This will dislodge some of the powder in that direction and cause it to activate, creating some kind of channeled ranged effect. While not enough powder is lost to matter, this kind of violence to the crystalline structure will eventually deplete its power and the mana currents inside it will dissipate.
Soul Mirroring / Summons / Quartz
Since energy can be turned relatively easily into matter, various magical techniques over the centuries have developed to exploit that. One of the ways is to create something known as "shadow matter", which functions similarly to matter but uses way less energy and is also less permanent.
Central to this mechanic is
Quartz, which is less a distinct material and more just a way that various things form sometimes (leading to things like "Quartzing" to turn something into quartz, or "Quartzed X" to refer to X that has turned into quartz), particularly in Caves due to the lack of light.
Quartz has the property of being able to copy a miniature version of a physical object in its molecular structure, whether it's inanimate or animate. It isn't a perfect replication, but it's enough to allow a mage to then turn it into a shadow version of that object or creature. For inanimate objects this process is known as "Ghosting" while with animate things it's known as "Summoning". Meanwhile putting things into the crystal is known as "Mirroring" or "Soul Mirroring" respectively.
Soul Mirroring seems to be the most effective when a creature is closest to death -- soul mirroring healthy creatures or dead creatures tends to have really unpredictable effects.
There are some weird theological and metaphysical implications of soul mirroring, but overall the consensus seems to be that a new creature is born and only exists while summoned, though each time you summon a creature it'll be the same creature.
Scout and Mountable animals
These are similar to summons, but work a bit differently.
Basically, there's a variety of animals that have been domesticated for use in various tasks. These were already domesticated pre-shatterloop and after the Expansion, enough of them were still around (in some different variations) to re-domesticate them.
While you can find their eggs in the wild and train them yourselves, there's a guild that's been doing it a long long time and has the most specialized and trained animals out there. Whatever their prized animals are, they'll soul mirror it into quartz while healthy, modify the quartz a bit to add an "Igniter" and ship them out as items.
While these animals don't require mana at all, you only get a limited amount of uses before the Quartz shatters. The animals are also unusually persistent -- birds can be sent out and come back
years later so there's probably something quantum happening to keep them from taking on full form.
People that have tried to replicate the Guild's work have looked into why, but the Igniter is this dense web of spells and shadowed objects, and the Quartz itself is carved into symbols that have crystal powder rubbed into them. Whatever is happening, it's apparently extremely complicated.