Category Archives: Rocks and Minerals
Prospectors and investors moved into Arizona after the Gadsden Purchase of 1853. To obtain the silver and gold they hunted, miners dug into the sides of hills and into shafts dug down into the earth. Boom towns like Tombstone called to talented hard-rock miners world-wide, who came to Arizona to find work and a future underground.
My father, my grandfather and my great-grandfather all worked underground in the mines of Bisbee, Arizona. I grew up listening to tales of the dangers and excitement of the mines. The near-misses, the rescues, the mammoth roaches and the temperatures. Two thousand miles of underground tunnels hollow the earth beneath Bisbee and the surrounding countryside. Sometimes Dad worked the night shift and we would go pick him up after work still in the dark. The daily afternoon blast siren was a normal occurrence. Every Bisbee child was well-versed in blasting cap safety.
I recently taught several groups of first graders a bit about Arizona geology, and was surprised to realize how little students today know about mining. “Who can tell me what a mine is?” I asked. The quick response was, “like Mine-Craft?” I realized it will be a large task, helping Arizona’s future know about Arizona’s past.
Please take time to enjoy this terrific video presented by the City of Bisbee, the Bisbee Mining and Historical Museum and the Bisbee Queen Mine Tour. Watch the video here.
Underground miners were certainly aware of the monetary value of the silver, gold and copper that they mined, but they also were awed by the beautiful caverns formed deep underground and covered with the secondary forms of the ore they blasted, shoveled and hauled up from the mines. These often take the form of delicate crystals with wonderful colors. As a child I was lucky to visit one such crystalline cave. In 1997 the Smithsonian Museum in Washington recreated one of these Bisbee caverns in the Museum. I keep a copy of the book commemorating it in my rock case, Treasures of the Queen by Richard Graeme.
Q is for Quartz
Quartz is the most common mineral of all. It is a form of silica. You can find Quartz that is transparent, or milky or translucent. There are also more varieties of Quartz than any other mineral. Some of the varieties are familiar names, such as Amethyst, Citrine and Agate. Rock collectors enjoy the hexagonal crystals which can be quite large.
Clusters of tiny crystals are known as “drusy quartz.” The most commonly seen chunks of quartz in Arizona are milky white and massive (not crystalline), also known as “bull quartz.”
Arizona prospectors have long looked to Quartz as a possible sign of gold. Some Quartz veins may have gold filling the fractures in the Quartz. Sometimes gold is hidden in pockets of sulfide minerals such as pyrite in the Quartz. Gold panners sift through sand, which contains lots of Quartz, to sort out the heavy bits of gold from the debris.