Stardust is by far the most utilized of the three platonic compounds. It materializes out of the interaction between mind and magic, and thus has no physical form. However, it is possible for stardust, like both magic and mind, to be caught, reflected, or captured by matter. Hard, enclosed porous structures, or certain lattice shapes, are able to trap stardust structures and prevent them from decaying almost indefinitely. Common sources are bones and insect exoskeletons, though fossils and all living matter also contains small portions.
Stardust pendants are mostly heirlooms and status symbols, though more practical uses like simplified telepathy are being explored and refined. Production of these pendants involves alchemizing certain mineral spirit distillates that then act as high-density stardust nets. As the distillates are saturated, they solidify, and turn from murky clear to the signature white-blue ribboned gemstone appearance.
Death magic is a poorly understood, dangerous, and uniquely regulated practice. Used offensively, it is capable of poisoning one's spirit; even a small cut caused by death magic can lead to undiagnosable sickness and death if not properly handled. However, first any death magic must go through the caster, and without proper care can easily kill them long before any proper spell is cast. In more accepted use, death magic can excite trapped stardust, allowing the user to commune with the previous owner, and even share experiences with others. Atherian death mages tend to work in bone libraries, giving their own lives to bring people closure.
Necromancy is, conceptually, quite simple. Attach some kinesis enchantments to a puppet, and generate a simple mind capable of controlling the kinesis and following basic directives. Bones are most often used for the puppet simply because they are light and don't require much crafting or refitting — bones are already made to fit together. In practice, magicking a control mind into existence with the proper parameters is touchy, and kinesis enchanting a puppet is a very fiddly process. A side effect, however, is that this magic mind then generates excess amounts of "blank" stardust — stardust that is structurally uncomplicated. This fills out any stardust nets quite quickly, flushing out more complicated structures that then decay. (This also occurs in the bones of living creatures; older experiences encoded in the stardust get pushed out as new ones emerge. This means that, while the half-life of free stardust is only a couple minutes, the half-life of living bone stardust could be up to a year, depending on the size of the net.)
Stardust is often thought of as a component of soul, if not the soul itself. It holds the memories of a person in their bones, long after they die. Death magic, apart from being dangerous and often monstrous, is a method of reconnecting with the dead through stardust, re-experiencing them again, and a chance to learn what they might have taught. Outside of bone libraries, necromancy is very rarely shunned, and not seen as inherently harmful. Inside of bone libraries however, necromancy is an open flame in the archives.
