Crystal, Gem, or Mineral?
The standard states that Crystals are nutritive elements for at least one living specie, or reactive minerals. Gems are all mineral used as money by at least one country. Mineral forms the rest of the non-living physical things on Dracca.
Porous stone used to clean up scales, furr, and feathers. A creature just has to stroke the stone, and the porous particles will stick to the dust and gluying substance. These substance are then easy to drop.
White mineral that can be shaped on demand. Then, it is used as a stone paper, for writing or drawing.
Purple mineral, very resistant like diamond, but way easier to find. Often used for blades and sharp tools.
Amer and chocolated crystal, not very nutritive but that can gives back some energy instantly.
Green crystal, very tasty, and appreciated by Plant and Ground dragons.
Colorless crystal, highly nutritive, and often taken for dessert.
Crystal that can bend space around it, meaning it has anti-gravity properties. Very wide spread on Insularyuu, in the Dencrag, where it forms floating islands.
Colorless crystal that alters the air around it, leaking slightly blue vapors. These vapors can numb dragons.
Red crystal that can give back some strength to some living creatures like weakened dragons. It cannot get someone back to life, but it can be used in the gamebooks to get back 1 Health point per read section.
Beautiful pink crystal that can give a bonus of 3 Skill points if used right before a fight.
Crystal used to seal a deal with some other dragon or creature. The other creature you're trading with will wear this special crystal (on a necklace or a bracelet), and will only be able to remove it once their part of the deal is done. So this is often used in tradings, but should be avoided in diplomatic relations, because it means you actually don't trust the other's words and have to use this crystal as an insurance.
Crystal that will emit a yellow light after being charged with some energy.
This light slowly fades out along time, making this crystal a great way to measure time.
Karlexia often use it to time her flying and running, and beat her own records.
When brought to daylight, this crystal heats up very quickly, allowing to set things like wood on fire. Its name comes from ogien (Polish, fire) and ignis (Greek, fire).
Black crystal that highly reacts to the daylight. The hexagonal structure of the submolecular elements in that crystal makes it very resistant to pressure, but the extra atoms between the main crystallographic layers weaken its internal structure, so the crystal can easily be cut in thin slice. Thus, these same intermediate atoms gives this crystal a completely black color, absorbing not only the visible light, but also a large part of the infrared frequencies too. Exposed to the daylight, it can then accumulate a lot of energy, leading to violent implosion if that energy is not properly released. That charging time depends on the daylight intensity, but can be consider as around an hour per Ovail. It is part of the same mineral group than the Oggìen, but when brought to daylight for few hours, it seems to explode without having heated up first.
Crystal that can turn water into vapor.
Small crystals that can be easily found underground. They emit a slight green light, like Verr does, since this planet is made of this crystal. They are well used as torch in caves.
Like the verrite, Vherrite (do not forget the "h") emits the same light but only after being bathed of UV rays. Depending of the polarity of these rays, the light Vherrite will emit can be green, purple, yellow, or any color inbetween. When left away, it will keep shining for few hours until it turns back to its normal transparent color. Vherris is almost only made of such crystal, making the satellite looks like a shining bright star in the sky when bathed in Opak's UV rays.