Jasper, chert, chalcedony, and flint are all forms of quartz, making their precise identification, like the rocks themselves, opaque. Chert is very abundant at my beach, Lake Michigan's Left Coast, and is represented by the caramel coloring in these samples. When chert bears the telltale red of jasper, it can be linked to Great Lakes … Continue reading Jasper and Chert
Glaciers carried all kinds of rocks to the southwestern shoreline of Lake Michigan. The famous Lake Michigan stones are rounded rocks of infinite colors and varieties. Identifying individual rocks and fossils on my beach in Ozaukee County, Wisconsin is a daunting task. It helps to know what might be expected given the geology of the … Continue reading Stromatolite
Luck is a matter of perspective. I have been lucky in different ways and different times in my life. As my self-education in geology expands, and my really nerdy hobby of collecting rocks extends to any available surface on my property, I consider myself lucky to live where I live. I live on Lake Michigan … Continue reading On Mother’s Day: What Luck!
Jasper is basically chert with red tones owing to hematite (iron ore) particles. The red can be imagined as rusty iron ore. Any jasper in this area is very old—Archean or Proterozoic (4 billion to 541 million years ago). Its presence reflects an early time in Earth's history when the atmosphere and ocean contained no … Continue reading Jasper
Green jasper with stromatolites