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I learned history in a traditional school program. We studied California history in the fourth grade and US history in the fifth grade and, in general, history was organized and presented by geography in expanding circles.
When I was taking courses in the history of Western Civilizations in college I found that I knew a lot […]

Amazonite has a soft green to blue green color, often with thin white streaks interlacing the green. It forms blocky prismatic or tabular crystals with angles that are not quite ninety degrees. Because of its natural beauty it is used to make jewelry and other ornamental objects. Amazonite has a glassy iridescence and ranges from […]

The formation of Geodes takes place over millions of years and involves several different geological processes.
Hollow Rocks
So, let’s start at the beginning: how do you get a hollow rock with lots of sparkling crystals inside? Geodes start their lives as a hollow bubble inside a layer of rock. The bubble could be from air inside […]

The Triassic Period begins the Mesozoic Era. The mass extinction event at the end of the Permian period ended 90% of the species on earth at that time. The plants and animals that survived would repopulate the planet.
The Age of Reptiles
The Mesozoic Era is called the Age of Reptiles. But that only tells a small […]

The Mesozoic Era begins at the end of the Permian Period. Mass extinction had eliminated most of the species of life that had existed throughout the Paleozoic Era.
The Continents
At end of the Paleozoic Era the land that would become the continents of Europe and Asia crashed into North America. By the time of the Mesozoic […]

Sedimentary rocks are classified as clastic, chemical, and organic sedimentary rocks.
The rocks in each group form by completely different processes.
Clastic Sedimentary Rocks
Clastic sedimentary rocks are formed from sediment. Sediments are tiny broken bits and pieces of rock that settle out of air or water.
Weathering
All rocks are subject to weathering. Weathering is anything that breaks the […]

The Paleozoic Era is seen in the fossil record as an explosion of life forms. The Cambrian Period marks the beginning of an era with thousands of new life forms in the ancient seas. Prior to the Cambrian period fossils are extremely rare but after about 540 million years ago the fossil record shows many […]

Igneous…ignite! And that’s just what happens when igneous rocks form. Fiercely hot molten rock from deep inside the earth pushes its way out and lights everything in its path on fire. As the firey liquid cools, it forms igneous rocks.
Rock types are organized, or classified, according to how the rock formed. It’s a pretty simple […]

Mineral identification is done by checking for certain properties of minerals. Because each mineral has its own unique set of physical properties we can test a specimen and find out how it exhibits these properties. This list of characteristics along with a good field guide will improve your chances of identifying mineral specimens.
Some of the […]