Several crystals found on this planet have supernatural properties. Only a dozen of them, all of which have healing magic powers, have been well studied, but others may have undiscovered abilities.
Three of the studied crystals cause a feeling of confidence or arrogance, and three of them cause a feeling of relaxation or apathy. It depends on how ‘charged’ the crystal is. The more charged the crystal, the stronger the feeling. These crystals have the ability to heal different systems of the body, including the skeletal system, the circulatory system, the respiratory system, the muscular system, the nervous system and the digestive system.
Each quartz crystal has a non-quartz counterpart with the opposite magical powers. Three of them can cause a feeling of anxiety or fear, and three of them can cause a feeling of anger or obsession. Again, the feeling depends on how charged the crystal is. They can also damage whatever their quartz counterpart can heal.
For example, citrine increases confidence, but can also heal the respiratory system (the lungs, throat etc). Performers regularly wear bolo ties and chokers with citrine to boost both their voices and their confidence on stage. On the other hand, topaz causes nervousness and the more it’s charged, the more intense the feeling gets, rising to fear and eventually terror. It also damages the respiratory system if one tries to use it medicinally. Aside from their healing properties (which not all gems possess), they are used for many aspects of Imperial life. The most expensive pistols are ‘quartzlock’, guns that use an unusual property of quartz, piezoelectricity, to produce a spark to ignite the gunpowder, as opposed to the common flintlock pistols. Imperial nobility, and the nouveau riche, are often bejewelled in expensive crystals that have been cut by artisans into beautiful shapes.