Tuesday, April 2, 2013


We all have likely gazed upon one of the wonders of our planet and found ourselves asking, "How did that get here?" Legends and stories explaining rock formations, crystals and geologic features have been circulating for ages. One such story is the legend of the "apache tears" stones.

According to the legend, in 1875 the US army found a secret path up an escarpment (now called "Apache Leap Mountain") near Superior, Arizona where a group of Apache warriors was hiding. In a surprise ambush, most Apaches were killed. A group of 75 Apache warriors chose to leap to their death from the top of the escarpment cliff to avoid being captured by soldiers. The families of the Apache warriors wept when they received the news of the tragic deaths. Legend says that ...the tears from the families turned to stone as they hit the ground, forming the apache tears. Many believe the stones bring good luck to those that carry them today. Although it is a touching story, science and history tell us something different about the origin of these stones.

Apache tears are actually merikanite obsidian nodules formed when lava cools in a very short time. The rapid cooling does not allow crystals to form, resulting in volcanic glass. The nodules vary in size from around 0.5 to 5 cm (peas to baseballs), and are often found in a perlite matrix near Superior, Arizona. Perlite is another type of volcanic glass with high water content that is very light colored, instead of dark, like obsidian. It expands 7 to 15 times its volume when heated due to water loss, and is mined for industrial uses such as insulation and cement. Apache tears appear to be an opaque black color, but when held up to a light, they are translucent and often a shade of brown.

I personally find the story of extremely hot lava shooting to the sky and rapidly cooling to form obsidian nodules to be an exciting story, too. It is a story of science, not legend, but still a very good one.






Photo showing both polished and rough "apache tears" obsidian nodules, Soleil Johnson


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