I’ve processed some photographs from a recent trip to the Raleigh Museum of Natural Sciences on June 4th, 2010. I’ll just string this into a long post of photos and comment on them as I go along.
In these photographs, the legend plate is located underneath each display. Each photo will open to a higher resolution version in a new window. I didn’t rotate these guys, or dress them up all nice ‘n pretty like, so please go easy on me!
Mineralogy is a fascinating sub-discipline of geology. It is technically rigorous with it’s chemistry, yet it still possesses the mystique of medieval alchemy. Identifying minerals using field tests can be a challenging exercise fraught with easy pitfalls. For example, one should avoid using mineral color as the sole identifier. Once long ago, I was handed a sample of halite to identify during a laboratory mineralogy exam. It was a cubic sample [about 4 inches per side] with well-worn faces, edges and corners, and it contained a cloudy azure blue inclusion. Everyone thought I was stumped until I gave this sample a big old lick with my tongue. They were flat-out astonished as I gently placed the sample back into it’s tray. I think that was one of three times I had ever seen Dr. Mumpton smile. Just don’t do a taste test on certain minerals, like orpiment or cinnabar.
So let’s take a look at some colorful minerals of North Carolina…
Hiddenite, tourmaline, quartz, rutile, beryl, and aquamarine.
Tourmaline, azurite, limonite, fluorite, and pyrite.
Meteorites!
Aquamarine, apatite, spodumene, bikitaite, orthoclase, beryl, fairflieldite, and hyalite.
Quartz and amethyst (purple quartz)
Garnet, emerald, tourmaline, citrine, aquamarine, beryl, kunzite, and kyanite.
Garnet. Common out west in the foothills and mountains from metamorphism.
Sapphires and rubies. Purdy.
Emerald and beryl. These are purdy too.
Gold! Money, Baby.
Calcite, fluorite, and siderite.
That’s pretty much it for the picture show. A low tech presentation here; however, when we come across any of these minerals in the field we can use this post as a reference point and discuss what the minerals tell us about the big picture. Once we get into the nitty-gritty of the mineral geochemistry, we can ascertain what types of environments the rocks surrounding these minerals “lived in”. Then we can, for lack of a better phrase, back-engineer what was going on geologically in a particular region in a bulk sense.
