Mineral meme meta-musings
Yesterday's mineral meme spread like wildfire!
Brian at Clastic Detritus, Kim at All my faults are stress-related, MJC Rocks at GeoTripper, the Lost Geologist, Chris at Highly Allochthonous, Dave at Geology News, me here at NOVA Geoblog, Silver Fox at Looking for Detachment, ReBecca at Dinochick Blogs, and A Life-Long Scholar at Musings of a Life-Long Scholar all followed the inaugural post by Chuck at Lounge of the Lab Lemming in offering a list of fifty minerals they thought others should see before they die...
It's interesting to see the different ways people interpreted the point of the exercise. A lot of folks copied Chuck's list and then changed the formatting (bold, italics, etc.) to match their experiences with the minerals, while others of us made our own list of what we considered important. This latter approach was the one I followed, but I confess to copying Chuck's list and then going through it to figure out which ones I felt deserved to be in the "top fifty" based on my own experiences. I deleted some, and added new ones in their place. I wonder if I would have gotten a different list if I had started from scratch. I'll bet I would have come up with some different minerals, like chlorite. So far as I can tell, chlorite didn't make anyone's list... but I would argue it's a pretty important mineral, especially in the Appalachian mountain belt. Given the option to revise, I'd probably drop azurite off my list, and put chlorite in that spot instead.
So let me issue a new challenge for my fellow geobloggers... Which five minerals do you think are the most important ones to know, and why? In other words, if you had to introduce a non-geologist to just five of the earth's multitudinous building blocks, which ones would you choose to share, and offer a justification for each.
Mine:
1.) Quartz: Toughest major (zircons are minor) constituent of the continental crust, most stable at Earth-surface conditions of temperature, pressure, humidity, etc. It's pretty much at equilibrium at the surface of the Earth, so while feldspars and amphiboles and what not break down into clay and rust and ions, quartz sticks around unchanging. Hence, mature terrigenous sedimentary rocks contain a high proportion of quartz.
2.) Clays: Ditto: stable at the Earth's surface.
3.) Plagioclase feldspar: The most common mineral in the Earth's crust. Why? It's made of the most common elements in the Earth's crust, and is versatile in its composition, depending on what ions are available to fill in the appropriate gaps in its crystal lattice (K, Ca, Na).
4.) Olivine (also maybe Garnet, Spinel & Perovskite?): Major constituent(s) of the mantle, the most volumetrically significant portion of our planet. Compared the portion of our planet that is ultramafic, the quartz and clays are diddly-squat. We may not live in the mantle, so it's less familiar... but Earth is mostly mantle, so it's important to know what minerals make it up.
5.) Ice: Possibly the mineral we encounter most frequently in our lives, and for many people a surprising member of the mineral list. Ice has played a major role in Earth history (glaciations in the Paleoproterozoic, Neoproterozoic, Paleozoic, and Pleistocene), the important role of ice in determining sea level (of consequence in the modern day's episode of climate change), the usefulness of ice melting/freezing in teaching about other minerals melting/solidifying, the unique nature of ice being more voluminous (lower density) than liquid water (which essentially has allowed freshwater ecosystems in temperate climates to survive, because they freeze from the top down, rather than the bottom up) and the fact that ice helps make a margarita the splendid thing that it is.
What are your Top Five?
Brian at Clastic Detritus, Kim at All my faults are stress-related, MJC Rocks at GeoTripper, the Lost Geologist, Chris at Highly Allochthonous, Dave at Geology News, me here at NOVA Geoblog, Silver Fox at Looking for Detachment, ReBecca at Dinochick Blogs, and A Life-Long Scholar at Musings of a Life-Long Scholar all followed the inaugural post by Chuck at Lounge of the Lab Lemming in offering a list of fifty minerals they thought others should see before they die...
It's interesting to see the different ways people interpreted the point of the exercise. A lot of folks copied Chuck's list and then changed the formatting (bold, italics, etc.) to match their experiences with the minerals, while others of us made our own list of what we considered important. This latter approach was the one I followed, but I confess to copying Chuck's list and then going through it to figure out which ones I felt deserved to be in the "top fifty" based on my own experiences. I deleted some, and added new ones in their place. I wonder if I would have gotten a different list if I had started from scratch. I'll bet I would have come up with some different minerals, like chlorite. So far as I can tell, chlorite didn't make anyone's list... but I would argue it's a pretty important mineral, especially in the Appalachian mountain belt. Given the option to revise, I'd probably drop azurite off my list, and put chlorite in that spot instead.
So let me issue a new challenge for my fellow geobloggers... Which five minerals do you think are the most important ones to know, and why? In other words, if you had to introduce a non-geologist to just five of the earth's multitudinous building blocks, which ones would you choose to share, and offer a justification for each.
Mine:
1.) Quartz: Toughest major (zircons are minor) constituent of the continental crust, most stable at Earth-surface conditions of temperature, pressure, humidity, etc. It's pretty much at equilibrium at the surface of the Earth, so while feldspars and amphiboles and what not break down into clay and rust and ions, quartz sticks around unchanging. Hence, mature terrigenous sedimentary rocks contain a high proportion of quartz.
2.) Clays: Ditto: stable at the Earth's surface.
3.) Plagioclase feldspar: The most common mineral in the Earth's crust. Why? It's made of the most common elements in the Earth's crust, and is versatile in its composition, depending on what ions are available to fill in the appropriate gaps in its crystal lattice (K, Ca, Na).
4.) Olivine (also maybe Garnet, Spinel & Perovskite?): Major constituent(s) of the mantle, the most volumetrically significant portion of our planet. Compared the portion of our planet that is ultramafic, the quartz and clays are diddly-squat. We may not live in the mantle, so it's less familiar... but Earth is mostly mantle, so it's important to know what minerals make it up.
5.) Ice: Possibly the mineral we encounter most frequently in our lives, and for many people a surprising member of the mineral list. Ice has played a major role in Earth history (glaciations in the Paleoproterozoic, Neoproterozoic, Paleozoic, and Pleistocene), the important role of ice in determining sea level (of consequence in the modern day's episode of climate change), the usefulness of ice melting/freezing in teaching about other minerals melting/solidifying, the unique nature of ice being more voluminous (lower density) than liquid water (which essentially has allowed freshwater ecosystems in temperate climates to survive, because they freeze from the top down, rather than the bottom up) and the fact that ice helps make a margarita the splendid thing that it is.
What are your Top Five?
5 Comments:
I had a hard time deciding between olivine and plagioclase. When it came down to it, I decided that, even though plag is the most common mineral in the crust, it's too hard to tell from k-spar and nepheline. (It's still in my intro lab, but I'm more likely to make students identify other minerals in a quiz.)
Ice is a good addition. I think I would still leave calcite, though. Maybe I would take out pyrite and put ice in.
Thanks for the nice suggestion!
Picking just 5 minerals feels both easier and harder than 50. I couldn't even think of 50 minerals from the top of my hat (and therefore I didn't pick up that meme), but choosing just 5 really makes one think about their importance.
I agree, 5 was much easier on the brain cells and only took a comfortable 1/2 hour.(10 minutes writing and 20 minutes daydreaming about each mineral)
I chose five, after a bit of agony, in an excruciatingly long blog post. ;)
So, after a week or so, I finally wrote my top 5 up.
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