You are visiting the farthest east outcrop of almandine garnets
in North Carolina.
Garnets are one of the most common mineral groups in the world.
They are found on every continent, from the highest moutain to the
lowest valley. There are six major species of garnets, three very
abundant in North Carolina.
Garnets are classified by the major metallic ion in the forumula
and how they are formed.
Pyrope garnets are the most common group. These are dark colored
crystals and typically found in high pressure metamorphic rocks and
are rich in magnesium.
Grossular garnets are yellow to brownish hue crystals typically
found in contact with limestone or marble metamorphic rocks. These
garnets are rich in calcium.
Almandine garnets are deep purple to ruby red crystals rich with
iron and found in metamorphic kyanite and mica schist.
When minerals crystallize, typically, the smaller the crystals,
the faster the igneous rock cooled or the faster the temperature
and pressure was removed from metamorphic rocks. Another indication
of rates of change are the number of crystals. The fewer the
crystals, the slower the rock cooled.
This location is called Garnet Hill and has boasted of marble
sized gem quality crystals collected over the years. The bottom of
the slope has loose garnets that have washed out of the matrix. You
can find garnets still in matrix all along the slope.
To log this earthcache, find an area of exposed rock, and count
the number of garnet crystals you find in a 12 inch diameter area
(about the size of a paper plate. Measure the diameter of the
garnets you found.
Based up on what you have learned and what you observe, did
these garnets form quickly or slowly? Why do you say so? Email your
answers to log this cache.
Pictures are always optional, but posting one of your crew lets
others know you had a good time.
If you stay near the bottom of the slope, it is a terrain 1.5.
If you choose to ascend the slope or visit on a rainy day, the
terrain WILL increase.
I have earned GSA's highest level: |
|
Ranger Fox, Dammed Rodan and Night-Ranger had to subject
themselves to my rambling when we here here for the nearby virtual
and traditional caches. Thanks guys for letting me talk about this
spot and take time to gather the data for the EarthCache.