When we arrived our host, Lisa, gathered the kids around to talk about types of rocks. She explained the difference between igneous, sedimentary, and metamorphic rocks.
She explained how granite is an igneous rock that hardens underground. Since it hardens underground it is considered an intrusive igneous rock.
Next, she showed them a piece of obsidian. She told them that it hardens above ground. Therefore, it is an extrusive igneous rock.
She then explained how geodes are igneous rocks that formed due to gas bubbles in the volcano.
Sedimentary rocks are typically found near water or places that had water when the rocks were formed. They are made from mineral deposits being 'cemented' upon each other over time.
The kids learned that mica and talc are such rocks and they are used in everyday products.
The metamorphic rocks are those that go through many changes and found deep in the Earth. Marble started off as limestone and worked its way down in the earth where the pressure and temperature changed the limestone into marble.
She told the kids that glass and mirrors are made of quartz, sand, and water. The electronic chips used in all our technological devices contain quartz. This special quartz is only produced in Spruce Pine, NC!
She showed them that glistening rubies start out as plain looking brown rocks. Also, gems are measured in carats. There are two types of carats - rough and cut carats. Rough carats cost less than cut carats of course. This is due to the fact that typically only twenty five percent of a rough carat gem stone is pure enough to be made into a cut carat jewel piece.
After the lesson on the different types of rocks and gems, the group made their way to the panning area. There each student received a gallon bucket of mining material and began their search for gems. They had a good time finding the treasure!
Next, the group was split into boys and girls. We had almost an even number of each. One group went inside to do experiments on the different rocks and minerals. The other group picked out one of their gems to make a wire wrapped gem necklace.
In the experimental class, the students learned about rock classification. They used streak plates and hardness testing. They also checked to see if their rocks fluoresced.
The outing was a great way to learn more about geology and maybe piqued an interest for a future geologist!
