In the mineral identification charts (pp. 26-38), the minerals have been
grouped, first of all, on the basis of _luster_: the first group
includes the minerals that appear _metallic_ and _almost metallic_
(_submetallic_); the second group includes those that appear
_nonmetallic_. Next, the minerals have been arranged within the two
groups according to _color_.
After you have determined the luster and the color of an unknown
mineral, turn to the _Key to Mineral Identification Charts_ on page 25.
It will direct you to the proper mineral chart.
Mineral Charts 1 through 5, which include the minerals of various colors
with _metallic_ and _submetallic_ lusters, are subdivided according to
the _hardness_ of the minerals. To determine the hardness of a mineral
that has one of these lusters, you can make the following tests: