Crystal Faceting and related topics

[Thaidakar the Ghostblood]

I don't know if this is the right thread for this... but yeah. Alright, so I'm writing a book with a magic system that has to do with crystals. Different facets determine the strength and effect from the magic crystals. So, I've been doing research about it all and thought I should make a thread to talk about it here. I'll occasionally come on with a question about it for any people on the shard who happen to know things about these things. 

Here are a few things I was wondering about, how fast does the spinny thing (it's a technical term lol) have to be to facet a gemstone or crystal? Does it depend on the crystal or gemstone? Is faceting for gemstones different from crystals? Also, does anyone know about foot pedal powered gem faceting machines? 'Cause, the book I'm writing doesn't exactly have double A batteries to put into the things to make them work. 

Anyways, anyone got any answers or know anything about this?

[AquaRegia]

I'm a chemist by trade, so I know some things about natural crystals, less so about faceting gemstones.  There is definitely a difference; crystalline substances NATURALLY form faces and edges, and the geometric relationship between them is determined by how the individual atoms pack together.  So the shapes and arrangements of the facets of a natural crystal (e.g., quartz, pyrite, halite, etc.) depend solely on how the atoms arrange themselves according to the laws of physics.  My understanding of gemcutting is that the best cuts for a specific type of mineral will depend on knowing what that mineral "wants" to do (sometimes described as its "crystal habit"), but if you are willing to work hard enough, you can put any kinds of facets you want on anything, as evidenced by "cut glass": glass is naturally amorphous and has no crystalline nature, but you can make it look like a cut gem.

[platnumkid]

re: "Is faceting for gemstones different from crystals?"

gemstones generally are crystals, what makes them more desirable is all about human perception.  Things like scarcity, light refracting properties, hardness, colour, will all translate to making a particular crystal more valuable and therefore worthy of someone trying to show off with this particular chunk of the earth.

 

re: "foot pedal powered gem faceting"

I don't now anything about the kinds of speeds or forces you require to facet gems, but I bet with complex gears and forces of nature you can get to where you need go without the use of electricity.  Wind mills and water wheels can harness plenty of force and with gears you can translate that to some very high rpm's.