Structure of Minerals

Most minerals occur as crystals when conditions are suitable.  In most cases these crystals are too small and too spread out to be of any value in identifying a mineral.  In these cases special laboratory tests are necessary.  In larger samples, the shape of a crystal can be important in helping to identify the mineral.  We will not delve too far into the science of Crystallography here.  Instead, we will only refer to the common shapes that help us in the field.
The most useful structural help is the FORM or HABIT of the mineral.  This refers to the shape of the lump that you dig up.