Ryll
this type of spice was mined on the planet Ryloth, and was originally used in a number of medicinal ways. It was eventually smuggled around the galaxy for use as a recreational drug. In any form or usage, ryll was highly addictive and very dangerous. Most refined ryll had a blue color. Unlike rocks or minerals that grew in veins, ryll tended to bloom when it propagated, filling entire caverns with crystalline growth. This made mining ryll both easier and harder than its cousin, glitterstim. While the mines that contain ryll were often spacious and well-lit, they were also prone to cave-in due to the amount of space that was left behind after the ryll was excavated. Many ryll mines on Ryloth were large enough to accommodate entire cities in the excavated chambers, and these cities prospered as long as the ryll held out.