Hello,Peter. To address your comments in order, first let me state that the only native rocks anywhere near where I live are sedimentary. As I stated earlier, the local outcrops are from the Silurian (see attached photo--I think of it as "Springtime in the Silurian"--a site in Miami County, Ohio, about 3 miles from my home) and the only businesses involved in geology are quarries and gravel pits. I live in the watershed area of the Great Miami River, on land that would have been a massive riverbed when it was covered by glacial meltwater.
As for determining the iron content, let me explain about what resulted when I sent the same sample--the first cut piece-- to two "expert" institutions. The first, the Smithsonian Museum of Natural History, after a visual examination by an intern, sent me a letter claiming it was "a terrestrial metamorphic rock. . . .[with] no nickel-iron minerals." A few months later, New England Meteoritical Services, after collecting a fee for "testing," sent me a letter stating that it was "a weathered, iron-rich, fine-grained, igneous rock. . . .terrestrial in origin." In neither case did the examination use any equipment other than a microscope. And these people call themselves "experts"?
Finally, about using acid, as far as I can determine, the only types of meteorites that such testing is useful for are iron and pallasites, both of which I was able to dismiss as possibilities early in my research.
On a more personal note, I have fairly extensive fossil collections from the Ordovician Period (Caesar Creek State Park in Warren County, Ohio) and the Miocene Epoch (primarily teeth and bones from marine animals--Chesapeake Beach, Maryland). I also have a few "erratics" from the local dirt and creek/river beds. Expect some photos in the near future.
Also, let me again apologize for the delayed response--the department chair's main complaint about my master's work in English (many years ago!) was that I was too much of a perfectionist in my research, since I thoroughly study a subject before making any comments. My quirk did end up making me the local expert (at the time) on Australian Aboriginal Literature!
Hope this helps clarify things further.
Mike S.
On Sunday, April 3, 2016 9:15 PM, "Peter Rosenholm treelaw45@yahoo.com [geology2]" <geology2@yahoogroups.com> wrote:
Hi, I'm not a geologist but I have found many fossils and specimens. To me what you have looks like a metal c rock or a meteorite. We have a rock here that is very heavy called Cumberlandite, it is a proximate 65% iron, 30% titanium and 5% silica. The material came from a blow hole from deep in the earth a very long time ago and is on something as small as a 10 acre site on what is called iron mountain in Rhode Island. The material is magnetic as you seem to show with the small vial, I even made an iron slug in a crucible.
When I look at the "X" shape it is close to the angle on a meterorite that has been acid etched, but yours is curved. Have you had this acid etched? This I believe will show the effect of gravity on iron. I did this to some iron slap and it looked like grass growing as it solidified from the bottom up where it sat on something cold as it cooled and it was magnetic as well. Your piece looks smoother than my Cumberlandite but has the same dark patina. I will look up my microscope images and see if they look like yours.
Like a Kimberling pipe or like what we have here with cumberlandite, do you think you have a pipe near you? Peter
[Attachment(s) from mcswigart@yahoo.com included below]Hello, Lin. Sorry for the delayed response, but I've been dealing with seasonal matters.First, to answer your questions:1. Streak tests are negative for both materials in the rock.2. Hardness is around 4-4.5 for the lighter-colored matrix and about 7 for the intrusive and fused darker material.One of the things that I have been able to find out from what used to be the Geology Department (now known as Earth and Environmental Sciences, focusing on water resources--as I said, we have no real geology in this part of Ohio, except for fossils) at Wright State University is that this rock has gone through some sort of "shock," but no one in the department could determine anything else from the sectioned slide. When I had it professionally cut, the company also took some microphotographs under polarized and planar lighting--see attached.As for the idea that this could be granite, I have no doubts that it is not. There is a massive granite boulder about a quarter-mile from my house that probably weighs several tons--the part above ground is about 15' x 10', with the highest point about 4 feet. What it does look like, under 30x magnification from my pocket microscope, is the 30x microphoto of basalt in my college Physical Geology textbook. (Eucrite meteorites, incidentally, are often physically indistinguishable from basalt.)Like you, I began my college career as a geology major, after two summers working as a night auditor at Grand Canyon National Park Lodges on the South Rim of the park. My focus was more on historical geology and fossils, but I ran up against a couple problems in that math is a foreign language to me and the only people hiring geologists at the time were oil exploration companies, especially Aramco. (If you knew me, you would know that my working in Saudi Arabia would not have ended well!)I really hoped to attract the attention of geologists through this group, because, if I'm right about this, this could be a great opportunity to publish a scientific paper on what would be a unique specimen.Here's hoping that someone else in the group will take notice and give me some more feedback.ThanksMike S.
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Attachment(s) from Michael Swigart mcswigart@yahoo.com [geology2] | View attachments on the web
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Posted by: Michael Swigart <mcswigart@yahoo.com>
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