AboutC. Robert Reszka, Jr. Expertise I can answer any general geology question (rocks, minerals, stratigraphy, geomorphology etc.). My expertise is in the geology of the Michigan Basin, PreCambrian, Paleozoic and Recent. I can answer questions concerning mining and petroleum exploration and production and the laws concerning those activities. I can also answer questions concerning stratigraphy of the Michigan Basin. I will also answer questions about mineral and rock collecting in the Basin. I won`t be able to answer many specific questions on hydrology, geophysics or geochemistry. I may be able to answer very general questions in those venues.
Experience I have been working for the State of Michigan for 24 years as a Geologist and a Resource Analyst. I have experience with Subsurface Geology and Petroleum Geology, mining in Michigan, and Sand Dune Mining and Protection issues.
Organizations Michigan Basin Geological Society
Publications Decade of North American Geology.
Bedrock Geology of Michigan
Question Dear Robert,
Today I found a strange rock in my garden by coincidence. It is a small rounded rock that is completely silver in color. It's hardness is probably about 6-7 as it just about left a scrape with a steel blade. It does not react with acid and does not oxidize with the air. It has a couple of folds on top as if it was once a liquid and solidified. I have just finished my first year of geology in Ireland and have not seen anything like it in my first year. It may be a mica but I'm still skeptical as it does not glitter, it is more of a tin foil shine. If you could help me at all it would be much appreciated!
Kind regards,
Clare
Answer Hi Clare,
Good description. I'm going to assume you found this rock in Ireland since you went to school there so I'll have to say I don't know much about the rocks found in Ireland.
However, I HAVE seen specimens like that and I have found them to be metal slag; usually from places like foundries or factories that use metals (like automobile plants). It's color, hardness, and metallic luster all indicate slag. Also you mention "folds" on its surface. The folds are created, in slag at least, in just the same way as those formed in Pahoehoe lava. I'm sure you know what that is.
Without seeing it I can't be completely sure, but I'll bet it's slag.
If you'd like you could send an image to geologyexpert@yahoo.com and I'll see if I think it's something else.
Hope this helps.
Bob
