Septium

Septium (七耀石, sepuchiumu) is a grouping of seven types of gemstones, found and actively mined across Zemuria. Septium have been viewed as symbols of mystery since ancient times. Their value as a resource increased drastically when the technology to refine fragments of septium, also known as sepith (七耀石の欠片, sepisu), into quartz was developed. Larger chunks of septium are refined into jewels.