So many gems, so little time

My spring break is coming up soon! I plan on spending at least a few days out getting some new minerals. You could have probably guessed that would be my plan. My friends and family know how excited I am about these trips and have asked me to give them smaller, less awesome versions of the minerals I find. Please check back during the first full week of March because I will have several posts about where I go, what I find, overall impressions, and helpful directions. Seriously, one of the hardest aspects of planning these mineral-hunting trips is finding out a proper address or at least a good parking location. My plans are to travel in the mountains with maybe one stop in the foothills or piedmont.

Garnets (A²⁺₃B³⁺₂Si₃O₁₂)
*A represents Ca, Fe²⁺, Mn, or Mg
*B represents Al, Cr, or Fe³⁺
I got a handful of nice garnets last year with my cousin Connor. I have a greater appreciation for garnets ever since I did some more research on a whim a month or two ago on my own time. I did not have an assignment to learn more about geology and mineralogy–I just wanted to learn more. Garnets come in almost any color. I knew about some of the green garnets such as demantoid garnet and became fascinated by them. Grossular, tsavorite, pyrope, almandine, and spessartine are several other types of garnet which are also common. Garnets are colored by calcium, iron, and manganese. Garnets have a hardness of 6.5-7.5, so they are very desirable for jewelry or as an abrasive in powdered form. Almandine garnets are very common in North Carolina’s garnet-mica schists. A schist is a metamorphic rock which can have many different types of minerals within it. The rock which undergoes metamorphism in order to produce a schist is normally a felsic igneous rock or shale. Felsic igneous rocks contain more than 75% of a felsic mineral such as plagioclase, orthoclase, or quartz. These felsic rocks are characterized by being abundant in silica.

Kyanite (Al₂SiO₅)
I became fascinated by kyanite when I went on a hike with one of my professors to Crowders Mountain in Gaston County, North Carolina. This mountain is a monadnock which remains today because the surrounding landscape eroded away from it. It is a beautiful area which I have visited in every season. Crowders Mountain exists in Crowders Mountain State Park which will protect it in the future. Originally, people wanted to mine the kyanite which Crowders Mountain is full of before it became protected. Kyanite is a blue-grey mineral which has a hardness of 5 or 7 depending on the way it is cut. It is recognizable because of its color as well as because of its elongated crystals which look similar to columns. It occurs in the metamorphic rocks schist and gneiss as well as in igneous pegmatites. I think it is interesting that kyanite is used very frequently in spark plugs. It seems like a waste of a very beautiful mineral. I would LOVE to find some new kyanite. I definitely will not be trying to get any of the kyanite from Crowders Mountain. My sights are set on somewhere much more remote near the border of Tennessee.

Corundum (Al₂O₃)
North Carolina’s rubies and sapphires are very famous. That is a good enough reason for me to want to get some. Corundum includes the aluminum oxides called sapphires and rubies. Sapphires are colored based on the trace amounts of elements which are in them including iron, copper, and magnesium. Chromium is the element which makes a ruby red. So, a ruby and sapphire are the basically same thing. Both make excellent gemstones for jewelry because they are very hard (basically only diamond and “fake-diamond” moissanite are harder). You may have seen clear corundum (lab created, of course) used for a watch face so that it would not get scratched. Corundum crystals are easy to spot because of their hexagonal structures.

Wish me luck! I am very excited to find some beautiful specimens. Maybe I will even find something I can have cut!

I’m Amy

         

I have put up a few blog entries without really introducing myself. I guess it is better late than never! Since I started this blog I have enjoyed looking at the “site stats” about how people find my blog. I do not possibly know how so many people found it so quickly! I wanted to introduce myself to the people reading this in case anyone wanted to know my “street cred” as a blogger. I make these entries as science lessons disguised as stories about cool places to hike, about how to identify minerals and gemstones, and about sparking an interest in getting your own. I am currently completing a BS in Environmental Science. I did not come to college thinking that I wanted to be in this field. Too many tree huggers, psh. (Totally joking) I wanted to be an interior designer who specialized in sustainable design.

I absolutely loved Steve Irwin when I was a kid. (Didn’t we all?) When I started my blog my dad asked me to put a big picture of him up because he motivated me to be a scientist. Yes, I admire my dad’s curiosity, intelligence, and love for science for sure. His father, I call him Pawpaw, is one of the most amazing naturalists I know. I think he is fascinating because of how much he knows. He loves talking about all of it as well. I love to talk about things happening in the scientific community and telling people facts that they have probably never heard. Pawpaw knows every tree, every wildflower, and everything about everything else it seems. He can feed a squirrel a peanut basically right from his hand. He hunted frequently when he was younger (my dad did too) and rides his motorcycle up on the Blue Ridge Parkway in Virginia whenever he can. Hunters get a bad reputation I think. So many of them have an immense amount of respect for the animals they hunt. I love learning about plants and animals from him. By the way, take a botany class if you ever get a chance. Plants rock. A strawberry isn’t even a berry! Back to the point… Both of my parents grew up in Wild and Wonderful (the state motto) West Virginia. Oh yes, West Virginia. So many Environmental Scientists talk about mountaintop removal and how people and the environment are impacted by it. This state is beautiful to me. I love West Virginia.

Back to Steve Irwin…Steve Irwin’s conservation efforts absolutely inspired me when I was a kid. I had the shirts, tapes, games, and everything else it seemed. I watched his shows and was completely captivated by those animals. I definitely have a greater appreciation for his work now that I have a few years really studying Environmental Science under my belt. He was a “life lover”–someone who just enjoyed every moment and actually took the time to appreciate things that so many people take for granted.

I was blessed to travel throughout Australia for three weeks during June and July of 2008 after Irwin’s death. The whole reason I was interested in going there was because of him. I worked on a farm, went to the Outback, and snorkeled on the Great Barrier Reef. Something which stuck with me was just how huge everything in Australia is compared to where I live. The untamed wildness of that landscape awoke this part of me which craved adventure.

You can see that seeds were planted by multiple people. Why are you interested in geology? Why are you a scientist?

I always ask “why.” I always thought gemstones were interesting, so I started to learn more about them as a hobby. I am a gem snob. It comes in handy though when someone needs help buying jewelry though.

         

I enjoy reading the works of Muir, Thoreau, and Emerson. They are classics for a reason! I hike, often alone, because I like being able to hear animals and my footsteps with nothing else. I hiked and biked almost 200 miles for an internship last summer where I mapped trails with a GPS and wrote about them. I am very proud of this. I fixed my bike alone a mile away from anywhere. I got lost and found my way back by observing the landscape and navigating a terrible map. I had a complete blast.

My friends make fun of how I want to live off the land, hunt my own food, and give my kids nature names like Meadow and Timber Stone. I like identifying trees with my tree book. I like minerals, rocks, and soil. Much of what first caught my interest in being a scientist was for a simple reason, but the appreciation I have for the big picture is what keeps me going. I love geology and do indeed think “geology rocks,” and I’m just fine with how I study something which not too many people even contemplate. I love knowing about geology and minerals because it helps me see a bigger picture when I look at a landscape. We do not need to know the reasons why a landscape formed in order to have a great appreciation for it. There are plenty of things I do not know. I am just an undergrad after all. A lot of what I know is self taught. It’s that curious spirit.

Granite and Quartz

Granite is one of the most common types of rock in this area, especially in the North Carolina mountains. Not many crystal specimens form within granite because granite’s structure often prevents outward crystals from forming. This is not always the case, however. Granite is an intrusive rock which forms from slowly cooling molten material within the earth’s crust. The most common minerals found in granite are quartz, micas, hornblende, and feldspar (both potassium feldspars and plagioclase feldspars). These minerals, in addition to smaller amounts of other minerals, are what give different colors to various types of granite. Micas are often responsible for the shiny bits which are so commonly seen in granite countertops, for example. All igneous rocks, including granite, form from melted or molten rock called magma. Granite is also an intrusive igneous rock which forms underneath the surface of the earth and also breaks through existing layers of rock. Many mountain chains such as the Appalachian Mountains are formed with a lot of granite in them.

I took this photo of this vein of quartz which is clearly visible from the trail of Table Rock within the Pisgah National Forest.

It is particuarly interesting to me that a lot of granite is radioactive because of how much uranium is found in it. It is more radioactive than other common rocks, but the structure of granite also contributes to how much radioactive material can actually escape and pose a threat to the environment and humans. According to the Environmental Protection Agency, the likelhiood that radioactive material which is found in granite would actually pose a threat to humans is actually not as high as we would think after hearing such a statistic. This uranium does not often escape because granite is not very porous. On the other hand, it is interesting that the majority of uranium ore deposits worldwide are attributed to granite. I never knew that before doing more research for writing this blog post.

These small pockets of quartz are also visible from the Table Rock trail located within the Pisgah National Forest in North Carolina. Linville Gorge, where Table Rock is located, is an absolutely breathtaking area which is fascinating to study from a geologic perspective. So many millions of years of erosion are visible in the gorge. I love hiking here and traveling here.

I discussed quartz (SiO₂) in my previous blog post North Carolina Beryl in some detail, but it is important to go over some more aspects which make it form so commonly in granite and other igneous rocks. The hardness of quartz is 7, and it often forms six-sided prisms which end in six-sided pyramids. There is indistinct cleavage with conchoidal fracture. Indistinct cleavage means that the mineral has cleavage which is hard to even notice because it barely even occurs. Conchoidal fracture means that the mineral is very brittle and breaks without defined planes of separation. Additionally, the melting point of quartz is near 1670-1700°C. All of these factors make it easier for quartz to form in granite because it is hard and very stable. Its low density of 2.66 g/cm³ also helps it to form in granite because granite needs to slowly form underneath the surface in a deep area. This may not make sense because a low density of quartz would make it seem as if it would not form in a very deep area within the earth, but actually the granite mountaintops people see while hiking (such as at Table Rock where I took these photos) were heavily eroded. The cleavage and fracture of quartz prevent it from breaking apart or dissolving when it forms in granite as well. The other constituting minerals (micas, hornblende, feldspars, etc.) of granite form before quartz does, thereby allowing quartz to fill the remaining spaces in the granite.

North Carolina Beryl

North Carolina’s beryl is amazing. Yes, I’m starting out this blog with a blanket statement. Yes, I’m ok with that. Many gemstones come from the mineral material which has the most desirable aesthetic qualities such as size and clarity.

The beryl family of minerals (with its gemstones!) is named for beryllium aluminum silicate Be₃Al₂Si₆O₁₈. The silicates are the most abundant class of rock-forming minerals. Specifically, beryl is considered a cyclosilicate because it has a 6-link ring of linked tetrahedra. Ore-grade beryl is used with the manufacture of alloys once the beryllium is extracted. Gem-grade beryl is faceted or cut en cabochon in order to be used for jewelry.

Green beryl is known as emerald. The green color of emerald is due to chromium.

Light blue or greenish blue beryl is known as aquamarine. The light blue color of aquamarine is due to Fe²⁺ ions.

There are more colors within the beryl family such as white, colorless, red, yellow (heliodor-colored because of Fe³⁺ ions), and pink (morganite-colored because of manganese). These gemstones have a hardness of 7.5-8, thereby making them very suitable to be worn in jewelry. North Carolina’s beryl is most often found in pegmatites which are igneous intrusions with a lot of quartz, mica, and feldspar. Generally, almost all beryl is found in these pegmatites. Here’s the easy way to think about it: a pegmatite is granite. Quartz (silicon dioxide SiO₂) is easy to spot because it is one of the most common minerals on earth. Quartz forms hexagonal crystals which are characterized by having ends in double rhombohedrons. Mica is also easily characterized by its structure. It is a sheet silicate which easily flakes off similar to peeling sunburn. Feldspar is also a very common mineral (it makes up roughly 60% of the earth’s crust), but it may not be as easy to recognize compared to quartz. The hexagonal crystals of the beryl family are the best to look out for when searching for gemstones in North Carolina pegmatites. Anyone searching for beryl in North Carolina should first look for areas with pegmatites. It is much easier to find what an emerald or an aquamarine should be found in, trust me.

Hiddenite, North Carolina is home to the Emerald Hollow Mine. This is the only mine in the United States which is open to the public. I have not been here before and am therefore unable to say about whether it is worth the effort, but I definitely plan on visiting this mine sometime in the future. North Carolina is an amazing place to find gemstones, but I am wary of going to mines which charge admission and everything like that because many mines are “salted” with gemstones in order to keep people coming back year after year. It is simple enough to search online about which mines have been “salted” with gemstones. They are often really cheap gemstones bought overseas and either put into buckets or dumped in streams for the public to search through and hopefully find some fun minerals which can be faceted into gemstones.