Elements are substances made up of only one kind of atom.
Whatever form they take, when you break them down and break them down into smaller and smaller pieces, each one is made up of the same kind of atom. For instance, oxygen is only made up of oxygen atoms, mercury is only made up of mercury atoms, and gold is only made up of gold atoms.
Each kind of atom that makes up each kind of element is different, having different numbers of protons, electrons, and neutrons. Any substance that is made up of only those kinds of atoms is an element.
Below is a Periodic Table of the Elements. It shows all the known elements and gives their chemical symbol (for instance oxygen is O, mercury is HG, gold is AU), and the atomic number of each element. For more information on the elements, you can search for one in the search box at the top of the page.
Minerals are substances that are made up of only one kind of molecule. There may be several kinds of elements (atoms), or there may be only one kind of atom. In those few cases where there are only one kind of atom, a mineral, and an element are the same thing.
Quartz is also a mineral. Quartz is made up of molecules that contain two elements – Silicon and Oxygen. The molecules of Quartz all include one Silicon atom (chemical symbol Si) and two atoms of Oxygen (O). The chemical formula for Quartz is therefore Si02. The “2” after the O means there are two of them for every (no number) Silicon atom.
Each mineral has its own chemical formula, as Quartz does. For instance, the formula for the mineral Raygrantite (named after Pinal Geology & Mineral Museum’s founder) is Pb10Zn(SO4)6(SiO4)2(OH)2. Anyone anywhere who finds something with that chemical formula knows they have Raygrantite.
Each mineral usually has a typical form, often a crystal. The crystals form one particular way because of the shape of the molecules they are made up of. Pure quartz, for instance, always has the same shape, as seen in the photo here.
For more information on Pinal County minerals, you can follow that link, or search for a mineral name in the search field at the top of the page. And here’s some information on basic Mineral Identification
Rocks are substances that are usually made up of several kinds of minerals. When something we might call a rock is made up of one kind of mineral, it’s usually just called a mineral rather than a rock.
Each kind of rock is usually always made up of the same types of mineral. For instance, granite is a rock mostly made up of the minerals quartz and some kinds of feldspar, with some mica and amphiboles. There may be small amounts of other minerals in granite, but to be granite, those are the four that need to be in it. Any rock that is mainly quartz and feldspar may be called a type of granite.
The “grains” of the granite in the photograph are the different mineral crystals that make up the rock. The light grains are quartz, and the darker grains are feldspar. The other colors in the rocks are the various other minerals that may be part of the granite, particularly mica which is the third mineral in all granite.
In some rocks, you can see the minerals with just your eyes, for some others you may need a microscope to see them.
More on the Major Types of Rock
You can use the search field at the top of the page to get more information on some of the more common types of rock in Arizona.