enter image description here

What is this rock? UK origin, non metallic, heavy

  • 2
    $\begingroup$ Please read the guide for asking rock identification questions and edit your question to add the necessary detail (and fix your broken image link). $\endgroup$ – Pont Aug 3 '17 at 14:32
  • $\begingroup$ en.wikipedia.org/wiki/Coal_ball Coal ball maybe? I read about these recently. $\endgroup$ – Mike Aug 3 '17 at 14:37
  • 1
    $\begingroup$ The UK has an extremely varied geology (arguable the most varied of any country of the same size). Where in the UK? If heavy, then I would suspect something man-made. Naturally occuring heavy minerals in the UK are/include barite (this is NOT barite) in Scotland; and tungsten ores (which I don't know anything about) from Cornwall/Devon. $\endgroup$ – winwaed Aug 3 '17 at 18:02
  • $\begingroup$ Possible duplicate of What are these metallic nodules that were found at low tide on the UK south coast? $\endgroup$ – theforestecologist Aug 7 '17 at 15:36
  • $\begingroup$ @theforestecologist Not a duplicate: metallic vs. non metallic $\endgroup$ – Jan Doggen Aug 7 '17 at 18:50

Your rock is most likely a marcasite nodule. These nodules weather out of the chalk beds along the coast.

Here is a reference to UK chalk beds.

If you are interested, I would like to trade for one. I'll trade you a nice pyrite nodule I found here in northern Ohio near Lake Erie.

See this similar question: What are these metallic nodules that were found at low tide on the UK south coast?

  • $\begingroup$ worth adding, marcasite is non-magnetic even though it is make of iron and sulfur. $\endgroup$ – John Oct 8 '17 at 15:45

Not coal... coal is very low density, so wouldn't be "heavy."

Looks like an ironstone concretion. It looks suspiciously like a sectarian nodule (google it), but the only way to tell that would be to cut it open with a rock saw. (This would be a helpful thing to do, anyway.)


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.