Naked Science Forum

Non Life Sciences => Geology, Palaeontology & Archaeology => Topic started by: lrenno on 28/02/2011 00:19:49

Title: Need help identifying this strange rock
Post by: lrenno on 28/02/2011 00:19:49

I uncovered this buried in our backyard in Decatur GA.  It is an area were a lot of junk had been buried in the past.  This seemed like a rock (heavy like a rock) but had a couple of green dots on the outside.  I struck it with a sledge hammer and found this inside.  It is hard to tell from the photo but there are little thin flakes of what look like copper, the rest of the rock looks like a swirl pattern of greenish blue.  It almost does not look like rock to me... perhaps something that had been dumped and then solidified over time.  Anyone here have a clue about what this might be?
(https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fdl.dropbox.com%2Fu%2F1063879%2FDSC_0001.JPG&hash=e1d0a51708b7fd3b5af5541a969f9f9f)

Title: Need help identifying this strange rock
Post by: Bass on 28/02/2011 04:47:00

looks like copper carbonates in an iron oxide matrix.  green is malachite, blue is azurite.  matrix is a mix of quartz and iron oxide (hematite, limonite).

Title: Need help identifying this strange rock
Post by: Geezer on 28/02/2011 05:38:06

Hey! I had a shirt that looked just like that in the sixties.

Title: Need help identifying this strange rock
Post by: lrenno on 28/02/2011 14:21:22

Thank you for the explanation.  I take it this a natural occurring rock?  I have not seen anything like it here before so my guess is that it made its way into our backyard along with other rocks used for landscaping.  Now that I know what it is called I will look it up!  Thanks!

Title: Need help identifying this strange rock
Post by: traveler on 28/02/2011 14:28:22

For some reason, I can't see the picture? By the description from Bass it sounds like it probably came from Graves Mountain in Lincolnton, GA. That is an incredible digging site that is open to the public if you call ahead. There was a club dig over the past weekend and there were over 100 rockhounds.

Title: Need help identifying this strange rock
Post by: lrenno on 28/02/2011 14:33:21

Try a refresh, I saw the broken image as well..perhaps dropbox where I am hosting it had a hiccup.

Your response has me excited now!  My son loves all things rocks so we are going to have to look into that trip!  Thanks for that info!