noun 下载 🔗分享 长石, feldspar 矿物。 Any of a large group of rock-forming minerals that, together, make up about 60% of the earth's outer crust. The feldspars are all aluminum silicates of the alkali metals sodium, potassium, calcium and barium. Feldspars are the principal constituents of igneous and plutonic rocks. Examples : "Many granite countertops are made up of quartz, mica, and feldspars. " 许多花岗岩台面是由石英、云母和长石类矿物组成的。 geology mineral material science 与AI对话词汇游戏阅读练习