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.
Naturally occurring silicon is composed of three stable isotopes, 28 Si (92.23%), 29 Si (4.67%), and 30 Si (3.10%), with 28 Si being the most abundant. Out of these, only 29 Si is of use in NMR and EPR spectroscopy, as it is the only one with a nuclear spin (I = 1 / 2).