Intrigued by works of Neal Stephenson, and drawn by ideas such as "how does magic hold back the industrial revolution in our fantasy worlds?", and always pushing the idea that magic is deep, mysterious, unpredictable and potentially dangerous, I am inspired to create a new classification of magic-user in Golarion; the "Gemnomancer", or "Lapidarian".
It's still a budding school of study, even dismissed in many circles, but some learned scholars have begun to unearth what they believe to be new properties inherent in gemstones, and enhanced and focused by the works of accomplished gem cutters.
Based upon early discoveries by such renowned magicians and sages such as Xemne Arcturus, Ptolemex, and Eudorius Manfrenjensen, (as well as the Dwarf gemologist Urd Tsengusun of course), there is a modest and growing library of new properties being catalogued:
- Cut gemstones of certain varieties seem to "remember" emotional events that occur in their presence, and these events can be "recalled" and projected on the walls around the viewer with near-perfect clarity.
- Under the right conditions, certain events thus "remembered" can be relived, including the emotional and physiological reaction by the viewer
- Being able to recall the past, or record the present for future posterity could have far-reaching implications for the societies of Golarion
- Certain gemstones display distinctive magical properties of condition, with nothing short of destroying the stone capable of altering this state. Some sages have surmised the construction of some sort of logic engine using a construct devised of such gems
- It has been theorized that many of the mechanical wonders of Numeria may have some form of these "difference engines" within them
The two above ideas could have an incredible impact on the future, but I am open to other ideas too, such as how there could be more immediate and practical applications for adventurers, or what is possibly a better name than "Gemnomancer"...?
Check out Super Genius Games' Guide to Crystal Magic. Seems highly related to your idea, although iirc it deals mostly with divinations and healing.
Thanks Cheapy!