Fall fell

It almost seems that the weather read the calendar this year. Within hours of the official arrival of fall, the thermometer started its yearly decline.

I watched a fascinating report on the formation of the earth on tv yesterday. I also picked up, by accident, an introductory geology class from Boise State University. The Bible says there was a world before Creation. It was empty of life, but there was a lot of water and even more rocks. There are rocks in space, and once in a while one hits our earth. I'm curious about rocks.

Today I learned that quartz and obsidian are almost identical in terms of mineral composition, but their structure is vastly different. Quartz contains many crystals of various colors and shape. Obsidian is one structure. Scientists say it's just a matter of how rapidly the rocks cooled. They both came from volcanic action. Obsidian formed when some of the rock was heaved out of the volcano and rapidly lost its heat. Quartz took longer to cool. So the structure of crystals in rocks is determined by the cooling process.

I'd like to cook up some obsidian and quartz, but I don't know how I'd ever get my stove hot enough. I'll just have to learn what others think about rocks. Hey, I've got rocks in my head. Maybe I'll study them one of these days.