I have always thought rocks were interesting. I don’t know all that much about them. I just mostly enjoy the interesting beauty of them. I could easily learn about rocks, but I have a very long list of things that I want to learn, and I can’t learn them all at once. Mostly I am a casual “enjoyer” of rocks. With the Internet at my fingertips, I learn about the rocks that interest me.
Like many children, I always picked up interesting rocks that I found. I remember when I was a child, a neighbor spread pretty white rocks on his family’s driveway. My friends and I admired the rocks, and then noticed that some of them were sparkling with gold. We excitedly whispered, “Do you think they know there is GOLD in their driveway? Should we tell them???” I think we showed one of the rocks to one of our older siblings, who informed us that it wasn’t real gold. It was FOOL’S GOLD, “Ha, ha, you guys are so stupid.”
My husband and I spent our honeymoon along Lake Michigan. We walked along the beach and, yup, picked up interesting rocks. We found several that were plain brown with white cracks. We thought they looked like smashed chocolates with the filling showing through the cracks. They looked much like the rocks in the picture at the right.
As I looked for a picture of the rocks we found on our honeymoon, I just discovered that they are Septarian Nodules, locally called Lightning Stones. They are found on beaches in the lower west side of Michigan. They consist of clay cemented onto an iron mineral called siderite. These concretions form in part through bacterial activity. They become fractured and the fractures fill with calcite brought in by ground water. The results forms lightning like patterns on a dark background. Awesome.
What caused me to write about rocks is this picture I came across on the Internet. This type of rock is called Banded Chalcedony. I thought it was absolutely beautiful–a stunning work of art. I learned that Chalcedony is the form of Quartz that is compact and microcrystalline. It occurs in many different forms, colors, and patterns, and many varieties have been used as gemstones since antiquity. In the gemstone trade, the term Chalcedony is often used specifically to describe the white, gray, or blue translucent type of Chalcedony, but its technical term includes all additional varieties.
Pretty cool, huh?