darter
starting to shine!
Member since August 2017
Posts: 26
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Post by darter on Nov 9, 2017 23:17:15 GMT -5
I'm not sure where to start with something like this. It seems to have different minerals in it with all the different colors, textures, reflectance, and such. My daughter found it in a spring in our lake in Central WI. I took a video of it to try to give a better sense of the sparkle and angles. We'd like to cut it open, maybe cut some slabs, but I'd like to know if anyone has suggestions on what angle to take with the blade. Or would this sort of specimen be better broken down and tumbled?
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Post by rmf on Nov 19, 2017 11:32:24 GMT -5
Pic 2 shows a lot of quartz. Pic 3 shows some brown material that could be feldspar (weathered/stained) or something else. What county in WI was it found? have you tried to get a streak from the various parts of the rock. The rock shows Iron staining. Any metalic lusters (pyrite, hematite etc)? get streak from these. It does not appear to have been tumbled by the glacier so it is either from an outcrop or from the driftless area of WI.
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darter
starting to shine!
Member since August 2017
Posts: 26
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Post by darter on Nov 19, 2017 11:38:46 GMT -5
Pic 2 shows a lot of quartz. Pic 3 shows some brown material that could be feldspar (weathered/stained) or something else. What county in WI was it found? have you tried to get a streak from the various parts of the rock. The rock shows Iron staining. Any metalic lusters (pyrite, hematite etc)? get streak from these. It does not appear to have been tumbled by the glacier so it is either from an outcrop or from the driftless area of WI. Thanks for the input. This was in southern Waupaca County, so not the driftless area. Although now that I think about it, the spring is close to the shore. Someone reinforcing their shoreline with rocks could have dropped it into the spring.
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Post by rockjunquie on Nov 19, 2017 13:59:39 GMT -5
I don't know what it is, but in your video either you are popping a big batch of popcorn or you have tumblers running. Sounds cool- interesting soundtrack.
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darter
starting to shine!
Member since August 2017
Posts: 26
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Post by darter on Nov 19, 2017 14:32:59 GMT -5
I don't know what it is, but in your video either you are popping a big batch of popcorn or you have tumblers running. Sounds cool- interesting soundtrack. Lol. That's a tumbler running next to me. Didn't even realize it. Well the theory it was dropped in is a but less likely...my daughter clarified a few things... 1. There are no stones added to the shoreline close by. 2. The rock was embedded in clay about half an arms length into the spring, stuck into the side wall of the spring. To do the streak test, will the back of a porcelain tile suffice?
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Post by rockjunquie on Nov 19, 2017 14:36:36 GMT -5
I don't know what it is, but in your video either you are popping a big batch of popcorn or you have tumblers running. Sounds cool- interesting soundtrack. Lol. That's a tumbler running next to me. Didn't even realize it. Well the theory it was dropped in is a but less likely...my daughter clarified a few things... 1. There are no stones added to the shoreline close by. 2. The rock was embedded in clay about half an arms length into the spring, stuck into the side wall of the spring. To do the streak test, will the back of a porcelain tile suffice? Yeah, that should work.
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Post by rmf on Nov 19, 2017 21:06:06 GMT -5
Darter, If you found the rocks in the dark brown portion of Waupaca CO then there is a formation called Wolf River age where there was/is and igneous intrusion which has Granite, Syenite, gabbro and Anorthosite and some other stuff. The Quartz is consistent with this the image #3 looks like a bit of gabbro. these will give only white streaks. Gabbro is a rock made from the feldspar family which should streak white, quarts is too hard for the unglazed porcelain. Usually in the igneous soup that formed it there was some pyrite if you get a greenish black streek you probably have some. though it is probably weathered to the iron stains seen on the rock. most likely not gemmy but interesting.
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darter
starting to shine!
Member since August 2017
Posts: 26
|
Post by darter on Nov 19, 2017 21:29:40 GMT -5
Darter, If you found the rocks in the View Attachment dark brown portion of Waupaca CO then there is a formation called Wolf River age where there was/is and igneous intrusion which has Granite, Syenite, gabbro and Anorthosite and some other stuff. The Quartz is consistent with this the image #3 looks like a bit of gabbro. these will give only white streaks. Gabbro is a rock made from the feldspar family which should streak white, quarts is too hard for the unglazed porcelain. Usually in the igneous soup that formed it there was some pyrite if you get a greenish black streek you probably have some. though it is probably weathered to the iron stains seen on the rock. most likely not gemmy but interesting. That's a cool map, what's the source? Spencer Lake is about 3 miles north of the southern border and maybe 8 miles from the western border, so it looks like it falls more in the light brown area.
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Post by rmf on Dec 3, 2017 16:41:59 GMT -5
I just did a search on Wisconsin Geologic maps and then took a screen shot of the county I wanted.
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