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I found this in the ground at a job site in blue springs mo . Its purple with darker purple lines through it like growth marks on a tree. It is about the size of a large loaf of bread 7 inches across 4 inches thick and 6 inches long . It is very heavy for a rock its size i would say it may weigh 20lbs or 25lbs. I can scratch it with a pair of sizzors And it leaves marks easy a penny just scuffs surface ill show pictures of it dry and wet . Wanting to know what it is. Thank you.! The powder after scratching it us purple as well . Looks like there may be crystal on it. Quartz maybe. enter image description hereenter image description hereenter image description hereenter image description hereenter image description hereenter image description hereenter image description here

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closed as off-topic by Jan Doggen, user12525, Fred, Erik, gansub Aug 29 at 10:30

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  • "Questions about rock identification requests are off-topic. For more information, see the announcement on meta." – Jan Doggen, Community, Fred, Erik, gansub
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I'm almost 100% sure that that is Jasper, a form of agatised clay, it might be Cinnabar but I doubt it. The whiter crystals are probably silica, either as quartz or something cryptocrystalline, but they may also be calcite deposited at a later date.

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  • $\begingroup$ Thank you it doesnt break at the lines its very heavy and hard to chip $\endgroup$ – Casey mcelroy Sep 20 '18 at 17:28
  • $\begingroup$ @Caseymcelroy Sounds like Jasper to me. $\endgroup$ – Ash Sep 23 '18 at 12:33
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Your rock looks like one of the following:

  • Limestone: White specks might be fossil fragments. Use HCL to determine if the rock reacts or white specks react to the acid. In Ohio, I have found pieces of limestone nearly the same color.
  • Dolostone: Similar to limestone but will be weakly to not reactive to a simple HCL test.
  • Banded Quartzite: Metamorphosed quartz rich sedimentary rock. Most quartz is very hard and tough. Use a hammer and chisel and see if you can break the rock along a 'bedding' line. If the rock breaks easily, it was not quartzite. Wisconsin, Minnesota and South Dakota have occurrences of dark red quartzite that look similar.
  • Banded Jasper or chalcedony. The texture of your rock really does match typical jasper or chalcedony.
  • Hard metamorphosed sedimentary sandy shale to greywacke. I have seen similar rocks around the Bay of Fundy in New Brunswich and Nova Scotia Canada. That color of rock can be found throughout Canadian Maritime provinces.
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