Jujangjil
It is a rock composed of ammonite minerals rich in silicon, oxygen, and aluminum in geology. The word jucheongjil, which is a combination of silicon and feldspar, refers to brightly colored components composed of silicon, oxygen, aluminum, sodium and potassium among the components contained in rocks and magmas. Specific gravity is 3 or more. Common plagioclase minerals include quartz, muscovite, quartzite, and plagioclase rich in sodium. It is also used synonymously with acidic rocks such as rhyolite since the modern era, indicating igneous rocks containing more than 63% of silicon dioxide.