You are Coral, mafia hench. Your partners are Shiryu (Jet, Godfather) and rhapsdy2 (Pearl). You may speak with your partners at night to determine who should be killed, and who should make the kill. You win when your side outnumbers the rest of the town. Please confirm by PM. (Had to be followed up with a message describing the delay-effect on the kills.) [Kills by marring.]
You are Pearl, mafia hench. Your partners are Shiryu (Jet, Godfather) and Coron (Coral). You may speak with your partners at night to determine who should be killed, and who should make the kill. You win when your side outnumbers the rest of the town. Please confirm by PM. [Kills by shattering.]
You are Jet, Mafia Godfather. Your underlings are rhapsdy2 (Pearl) and Coron (Coral). You may speak with them at night to plan your target. YOU, however, are responsible for the final determination. You are also responsible for choosing who will go out to commit the actual kill. You win when your side outnumbers the rest of the town. Please confirm by PM. [Kills by shattering.]
You are Amber, Serial Killer. Unlike the rest of the gems in the case, you aren't even really a mineral; you're simply hardened (and really old) tree sap. Having to deal with this has left you standing on the edge of insanity. Every night, you may choose one person to target for elimination. Since your kill method (coating the target with sap) kind of obviously points you out, Emerald is available as a safe claim. You win when you are the only one left. Please confirm by PM. [Kills by gunk.]
You are Quartz, contact reflector. When under pressure, you emit an electrical charge, which repels night actions. Any night action aimed at you that requires physical contact to work will instead be negated, with a fifty percent chance of being performed on the person who targeted you. You win when all scum are eliminated. Please confirm by PM.
You are Ruby, cop. Because of a strange physical reaction between the ultraviolet lamps left on at night, and your crystalline structure, you glow brightly with a vivid red light during the night. By this light, you may look at another player and determine whether they are faceted or not; in general, unfaceted stones are scum. Be warned: your light is actually laser light, and may damage the person it's aimed at; choose your targets wisely. You win with the town. Please confirm by PM.
You are Obsidian, Vig. Once per night, you may choose someone to target for a kill attempt. You win when all scum are eliminated. Please confirm by PM.
(Had to be followed up with a message describing the delay-effect on the kills.) [Kills by marring.]
You are Amethyst, backup cop/doc. When the normal cop or doc dies, you will replace them. You are talented enough that, if both happen to die before you do, you may choose which of the jobs you wish to take on. You win when all scum are eliminated. Please confirm by PM.
You are Bloodstone, Reviver. Some night kills are marrings, delayed reactions which don't kill until the end of the day. These will be revealed at the beginning of the day, but only as someone who has apparently been lightly injured. You may choose, once every two days, to revive someone who has been targetted so. You win when all scum are eliminated. Please confirm by PM.
You are Alexandrite, mason. Your partner is Nox (Tourmaline). You may communicate with each other at night, freely. You may also each send one message to the other during the daytime, by way of the moderator. You win when all scum are eliminated. Please confirm by PM.
You are Tourmaline, mason. Your partner is Kain (Alexandrite). You may communicate with each other at night, freely. You may also each send one message to the other during the daytime, by way of the moderator. You win when all scum are eliminated. Please confirm by PM.
You are Sapphire, Doc. Each night, you may send in the names of up to two players you wish to protect. Please specify which is your first choice: Protecting this one costs you nothing even if they are targeted. If your second choice is targeted, though, you will die in their place. You win when all scum are eliminated. Please confirm by PM.
Now for the logic behind the gem/role pairings:
Ruby/Cop: That statement is actually true; I've seen a pair of pictures, one taken under ordinary light, and another under UV light. The ruby in the UV image was glowing such a vivid red that the facets on it could no longer be seen.
Sapphire/Doc: Seemed a logical connection after I made ruby the cop. The double protect stemmed from the fact that there are multiple versions of sapphire out there. Alas, Warpdragon didn't think to use his extra protect to guard himself night one.
Amethyst/Backup: Rubies are red, Sapphires are blue. A purple gem seemed to be the perfect backup for both.
Alexandrite/Mason and Tourmaline/Mason: Tourmaline shades between red and green within the same crystal. Alexandrite changes color between red and green depending on the light it's looked at under. Making the two a pair seemed obvious to me.
Obsidian/Delay-vig: As pointed out above, Obsidian is a type of natural glass. (Volcanic, to be precise.) As such, it should theoretically be able to scratch other stones. Please note that I paid no attention to the Mohs hardness scale when assigning these roles.
Quartz/Reflector: I've been toying with the idea of a reflective role since shortly after I found the site. Quartz made perfect sense (at least to me) because of the piezoelectric effect. There were only two roles that could successfully target Quartz: Ruby and Amber. Although any non-amber kill would fail, neither Warpdragon nor Darquiel could have protected him. Also, had darquiel turned cop, an investigation would have revealed that there was 'something strange' about Bacde.
Bloodstone/Reviver: Reviver may not have been the best name for this role, since it couldn't actually bring back someone who had fallen. It was just the best I could think of. Bloodstone, according to some versions of folklore, is capable of healing hemorrhages.
Amber/SK: Read the role description; most of my thoughts on amber went into it.
Coral/Hench and Pearl/Hench: Simply stones matching the pattern I'd decided on for scum. Along with the Godfather, Jet, the two were organic stones.
Jet/Godfather: Jet is basically gem-grade coal. It can be faceted, so it was a legitimate godfather type.
Please feel free to shout loud imprecations and limited abuse at my logic; I never got a chance to have someone help balance this, so it may not have been set up effectively. Any and all comments are welcome.