Another nice surprise from Adventure Publications!
Rocks In My Head
Yes, I'm still reading Minnesota geology, but but I received a complimentary copy, from Adventure Publications, of a stunning paperback titled The Storied Agate: 100 Unique Lake Superior Agates
The Mississippian period in Minnesota is like the two earlier geologic periods. Information is obtained from other areas as there is very little evidence left in the state. Warm shallow seas were probably homes to crinoids (sea lilies). Also, amphibians were likely to have lived near rivers, lakes and other wet areas. Land plants had developed, but not flowering plants.
I have discovered a new aspect of stone collecting that appeals to me very much. Suiseki is the Japanese word for viewing stones. That is, stones presented in their natural state and appreciated as works of art. The practice began in China, where the objects are known as scholars' stones, or Gongshi. The Koreans also have their variation of this art. There is is called seosuk. Western cultures have begun to adopt yet another interpretation of this type of artistic presentation. In Japan, it is often associated with bonsai. In Western culture this art is in its infancy and is still evolving. I hope to contribute to its evolution, now that I have discovered it.
I thought I saw a new store front business in town, and it was a rock shop. Then I thought to myself, I must be mistaken. Nobody in their right mind starts a rock shop. Wow. Did I really say that out loud? I have been fighting this attitude for years, and I've blogged about it and raved about it, and now I've fallen prey to it myself. Yesterday I found an ad in the classified section of the local shopper. I was right. Someone has started a rock shop downtown.
My parents had a rock shop. So did my grandfather. My parents were told in both subtle and not so subtle ways that rocks are a hobby, not a business. As I see it my parents were beaten down by this attitude, persistent and relentless,
until they believed it themselves. I often wonder why the nosy neighbors and others (I don't really remember who it was) couldn't have afforded them the dignity of calllng it a seasonal business. Which it was. Kind of like a resort. They would have felt much better about themselves. Confidence and support might have pushed their enterprize into a more viable arena. My parents were too poor for hobbies and they used every dime for living expenses. Sometimes I could cry.
People try to pull that s*** on me too. When somebody stops in and refers to my hobby I try to set them straight but my first impulse is to say &%#@$%^. And no, this isn't a hobby farm. This is where my grandparents made a living and raised seven kids.
A new rock shop in town! Competition? No, not at all. Just wind in my sails.
I am really bummed out on a trade transaction I made via the forum Dirty Rockhounds. One person was pleased with what I sent and recommended me for another trade. Another person didn't say anything. The third person was "dissapointed", and very sarcastic with me. Her reaction left me dumbfounded.
The last cabochon my 96 year old grandfather made was brown stromatolite which is not flashy but is very interesting. It is an 8 billion year old MN fossil, the earliest life form. Red stromatolites are considered gem quality. I sent her both. My parents and grandparents signed a waiver and went into the now underwater Mary Ellen mine to gather this material. Larvikite, from Norway, also known as Swedish blue pearl, is the stone we used to make both my grandfather’s and mother’s gravestones. A friend who works in mines has been to all 3 larvikite quarries in Norway. 90 percent goes to waste because it has to be cut at just the right angle to take advantage of the “sparkles”. My uncle made it into beautiful belt buckles. I could go on and on. Every stone has a story. Since she was so unhappy I offered twice to send out another box if she would send me her mailing address again. But I got no response. It makes me wonder if my family has been dealing in such worthless crap for over sixty years maybe we shouldn’t have been in business in the first place.
The same as with the Silurian, there is not a lot of evidence of activity from the Devonian period in Minnesota. An exception is a carbonate unit called the Cedar Valley formation in southern Minnsota. The material was deposited by the advance, then the withdrawal, of marine waters. Most of the fossil evidence has been obliterated. Elsewhere in the world there is fossil evidence of bizarre fish types, swamps and forests, and primitive amphibians. It is a fascinating era, for anyone who enjoys reading about the earth's history.
I have received two boxes of rocks and minerals in trade, from contacts I made at Dirty Rockhounds, a site for earth science enthusiasts. Beautiful quartz from SC (Diamond Hill Mine), and others from a collector in WV. Now I have to do a good job of selecting items for my end of the trade :)
According to the geology books, there are no Silurian rocks in Minnesota. Elsewhere there is evidence of primitive plant life, mosses and corals. There may have been vascular plants. But Minnesota was a barren peneplain covered by a very hot sea. The equator passed right through the middle of the state.
I am about to fill in gaps in my rock inventory with a few ordered items: turquoise in forms ranging from good quality cabochons to chalk to beads; carefully chosen fossils including coprolite, and my continuing acquisition of affordable examples of the traditional and alternative birthstones. I opened the tumblers and found that most of the materials have to go back in. Haven't gotten together with the "ladies" to do wirewrap yet. I gathered up all the white rocks for prep and painting during the coming winter...which unfortunately is on its way.
The rock record of depositions from weathering is well exposed in southern Minnesota. There are many sandstone formations, along with some shales, named after area towns. The Mt. Simon sandstone has rounded sands which indicate high energy deposition, strong waves and currents. The material contains quite a few brachiopods.
The Hinckley Formation is similar to the Mt. Simon but the latter contains more feldspar. The Eau Claire Formation is fine grained, suggesting that it was formed under quiet, calm conditions.
Galesville Sandstone is coarse grained, likely formed under high energy conditions near the shore or beach. The Ironton Formation contains silt as well as quartz and rests on the Galesville Sandstone, suggesting perhaps that the sea withdrew and redeposition under calmer conditions ensued.
The Franconia Formation is characterized by abundant glauconite, which forms on the sea floor under oxygen poor conditions. The Saint Lawrence Formation is characterized by carbonates but also contains silt, clay, and sand which indicate fluctuating conditions. Jordan Sandstone is coarse-grained and contains pebbles, indicating it was formed near a shore or beach. These formations are interesting as a record of the seas that once covered Minnesota.
Sweltering here a couple of days ago, but now it's cool and almost like fall.
No time or energy to read up on geology. We are expecting 300 barn guests and I want to have my shop looking decent in case some decide to visit it. I really could use a lot more inventory. When I rearrange things, blank spots appear. Today somebody visited my shop, a fine person I am sure, but he had a forceful way of asking questions, and I was at a disadvantage because I wasn't expecting it. Anyway, he asked how long I had lived on the property and I said all my life. He responded by speculating on how long a life I had lived, and he guessed accurately, which made me damn $%^&**ing mad. I'm used to people either underestimating my age or holding their tongue. Maybe time has caught up with me, or I have to get back on the treadmill, comb my hair when I get up, and wear make up not just for special occasions anymore. !@#$$%^^&&
I made a good trade the other day, jasper and hematite for copper and turquoise and similar ores including lead silver.
I haven't done any research I can blog about, unless I count a couple of articles sold to Mechanical Turk that were based on earlier research. I wrote about carnelian and crystalline quartz. I have a facebook page for my business now, and quite a few fans. I sorted through the newly opened small tumblers again, but a lot of that stuff has to go back in the polish. As usual, some were gorgeous and some are pretty rough.
If anybody at all is reading this blog, check out Hoffs Rock Shop on Facebook. I post different pictures than the ones on my site.
The Middle Cambrian is what we call the time period from 2500 to 1600 million years ago. It is important to the economic history of Minnesota, and to the development of this nation as an industrial giant. Why? Well, sometime during this era, the atmosphere changed from one rich in carbon dioxide to an atmosphere rich in oxygen. This happened because of the development of colonies of green marine plants. The oxygen released iron in the underlying rocks and deposited it as hematite (iron ore), which makes up the iron ranges in Minnesota. This happened world wide. The iron ranges on other continents have been determined, by geochronologists, to be the same age. Other interesting geological events happened in Minnesota around this time, including some mountain building, but this one was probably the most spectacular.
I opened up the small tumblers and found some nice Minnesota agates and other agate, jasper and quartz material. Also, I ordered tumbled rocks, to get more variety and to start making sure I have reasonably priced examples of all the birthstones. I started with January, and ordered garnet and rose quartz. Then put the rocks that needed more polish back in the tripoli powder. I still don't have road signs but I'm carrying on as if I did :)
My shop still exists both online and in real space but I am not in a mood to blog about mineralogy, paleontology, geology, metaphysics, stone healing, or anything like that. Two events have happened that have ground my business to a halt. It was barely chugging along as it was. I really can't afford to replace the road signs that were taken down. But even if I do, my inventory is mediocre, leading me to ask myself, why replace the signs? My cash flow problem prevents me from purchasing fill-in inventory for making my shop look more inviting and colorful and interesting. There are other ways to obtain inventory. Self collecting in the field. Trading with someone who stops in, or by mail. Processing raw materials on hand to make something new and different. None of these are as easy as putting in an order.
I have a pile of rocks that I can't do much with, so little by little I am painting on them. A native American artist stopped in the other day. He makes sculptures out of rock of all sizes from boulders to small hand sized pieces. I might not be able to do that but maybe I can make something.http://www.oliviahoff.com
Chromates are a source of chromium for electroplating steel, and are also used to make stainless steel. The most popular is crocoite which forms bright, attractive crystals of red, yellow and orange. Unlike tarapacaite and lopezite, crocoite is not soluble in water.
Tungstates and molybdates are always associated. They are important to industry as filaments in bulbs and tubes, and useful in nuclear reactors, to clad fuel rods. There are three main groups: wolframite, scheelite, and wulfenite. The only one that I am personally familiar with as a mineral is wulfenite.
I am finished with mineralogy for a long while.