mud - soil with mud, muck, or mire; The child mucked up his shirt while playing ball in the garden muck up, muck, mire begrime, bemire, colly, dirty, grime, soil - make soiled, filthy, or dirty; don't soil your clothes when you play outside!
Quartz is one of the most common minerals in the Earth's crust. It is made up of silicon dioxide (SiO2), otherwise known as silica. White sand is primarily made from quartz. Click here to find out more.
Almost 85% of the atoms in the crust are oxygen or silicon atoms, and as a result the vast majority of common (rock-forming) minerals are silicates -- combinations of oxygen and silicon primarily with the other six (most common) metals listed above. Pure silica or quartz consists of only silicon and oxygen.