 Sink
and Float Rocks: Students experience the density of rocks and minerals
first-hand. Students heft samples of pumice and scoria and guess if they are heavier
or lighter than water. Then they simply drop the specimens into a tank of water to test if
they will fl oat.
 Scratch & Sniff Minerals:
Students will experience minerals and rocks via their sense of smell. Smell
tells you that something important is happening when you scratch a rock or
mineral. Smelly minerals can indicate the presence of tiny invisible fluid inclusions
in minerals and rocks and give clues to their compositions.
 Mineral
Taste Test: Students will experience minerals and rocks via their sense of taste. Some common
minerals dissolve quickly and have a distinctive taste; others don’t dissolve, but
have a characteristic textures when tasted.
 Very
Attractive Minerals: Students will determine that some
minerals, rocks, and other materials are naturally magnetic.
 An
Acidic Reaction: Students will use a chemical reaction to test for the
presence of carbonate in calcite and limestone. By dropping a small amount of
an acid on these specimens, they will observe bubbles of carbon dioxide forming from
the reaction of the acid with carbonate minerals.
 It's
Useless to be a Resister: Students will observe that some minerals are natural electrical conductors while others
are good insulators. They use a simple electrical circuit to test whether a sample is
conductive.
 Tested
by Fire: Everyone loves fireworks and students often wonder how
fi reworks get their rich colors. Using the flame test, students can produce their own colored
flames and learn about fi reworks, minerals, and their common elements.
 Time
to Split: Students will break minerals and observe their cleavage
or fracture. How a mineral breaks depends upon the mineral’s structure. Cleavage
is an easily demonstrated property of minerals such as calcite, halite, and mica.
The Mineral That
Gets a Suntan: Exposure to ultraviolet light causes changes in
minerals. One of the lesser-known phenomena is tenebrescence, in which a mineral actually
changes color upon exposure to ultraviolet light (this is not the same as fluorescence). Using
an ultraviolet light, students can give a mineral a reversible “suntan.”
 Is
it Hot In Here: Radioactivity is more common than you suspect. Students
can detect radioactive rocks and minerals with a Geiger counter and investigate
the radioactivity of some household items.
 I'm
Seeing Double: Double refraction is easily observable in optically-clear
calcite. Students observe double refraction and prove that calcite not only refracts light to
produce two images, but that light passing through calcite is also polarized.
 Fire
from the Rock: Early settlers used flint and steel to start fires. Students can relive
the days of the early pioneers when they strike sparks from flint to make a fire.
Soft as a Baby’s Skin:
Every student encounters the Moh’s Hardness Scale in science class. The concept of
relative hardness is easily in theory but more diffi cult to demonstrate in practice. It is easier to
experience relative hardness at the soft end of the hardness scale.
 Glow
in the Dark Rocks: Formerly, demonstration of the fluorescence and
phosphorescence of minerals under ultraviolet lamps was possible only in a darkened
room. New, high-output ultraviolet lamps are much brighter than earlier lamps and
the resulting fluorescence and phosphorescence are bright enough, for some minerals,
to be seen even in a lighted room.
 Light Pipes and Frosted Rocks:
Fiber optic technology is the basis of our modern computer and telephone networks. Few
people know that natural fiber optic materials occur in the mineral kingdom. Students
can observe the fiber optic effect in minerals such asulexite.
 Wild and Cool Colors:
Everyone knows the fascinating play of colors that mark a good fi re opal.
A variety of minerals exhibit similar interesting optical effects such as
schiller, iridescence, and pleochroism. Students can observe these properties inhand specimens.
 How
to Bend A Rock: Students think of rocks as hard, inflexible objects but it is possible for
them to actually bend a rock or a mineral. Some rocks and minerals are elastic.
 Can
You Find The Real Diamond? If you purchase diamond jewelry, how do
you know you’re buying a real diamond? Students will learn how diffi cult it is to
pick out a real diamond from among fakes. If diamond simulants are hard to
distinguish from real diamonds, should you spend lots of money on real gems?
 The
Popcorn Mineral: Students take a small piece of unexpanded vermiculite, holding it with
tongs or long tweezers, and insert it into the flame of a propane torch. The vermiculite
expands rapidly to many times its original thickness.
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