The several days of light rains in Apex Canyon have washed a lot of fool’s gold down into the erosion control dams that cross the trail. Those portions of the trail glitter! Fool’s gold has a gold color that fooled many beginning prospectors from the ancient Greeks to the Colorado gold rush. It didn’t help that pyrite is often found in the same metamorphic rocks – like gneiss and quartz pegmatite veins – as gold. In the early days of the gold rush in Colorado, “green horns” (folks new to the west) would see a scatter of pyrite on the surface of the mud in their prospecting pans and think that they were rich. The old hands at prospecting knew better – while iron pyrite is very light, and stays on the surface of the mud, gold is very heavy and sinks to the bottom.
In fact, apart from their color, fool’s gold and true gold are about as opposite as two minerals can get. Chemists and geologists know fool’s gold as iron pyrite (FeS2). Where gold is soft, heavy and doesn’t rust (oxidize), iron pyrite is hard, light and rusts very easily. And when it rusts, it loses it’s glitter.
A Natural History Of Trail Ridge Road
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