removed from matrix - fossil, rock, ??

[Ramona]

I am enjoying learning about the rocks in our yard.  I found one that had something embedded in it, so I decided to try to remove the items from the matrix.  I brushed and cleaned it well with vinegar and water and then used dental tools to pick the matrix away from it.  How fascinating it was to see the matrix fall away - it was NOTHING like I expected it to be!  There were two items embedded - and they may have originally been one whole piece.  It is hollow and I have no clue if it is a fossil of some sort or a different type of rock that was embedded into a limestone rock.  It took hours to remove these two items, but it was worth it.  I did take some photographs along the way, but unless anyone is interested in seeing those, I will just post the end result.  These two photos are of the first piece to be removed. This first piece is not deep - it seemed like maybe a "top" to the other piece, although they were laying side by side in the limestone.  I have photographed both sides.  Measurements are about 1.5 cm x 2cm.   

Thanks!
Ramona

[Ramona]

Here are some photos of the second piece I removed from the limestone matrix.  This piece is hollow and also around 1.5cm by 2cm. I will add some more photos, too.

[Ramona]

More angles of the second item I removed from the limestone matrix.  Any idea what this might be?  

[Ludwigia]

Looks like a mineral geode of some sort.

[Ramona]

Just now, Ludwigia said:

Looks like a mineral geode of some sort.

I wondered about that!  Thanks!

[Bob Saunders]

looks like a Chalcedony geode. Try a Google search for images from your state. 

[Ramona]

5 hours ago, Bob Saunders said:

looks like a Chalcedony geode. Try a Google search for images from your state. 

Thanks!  I will go research now that I have a direction!  I am wondering if I should try to remove some more of what looks like matrix on the outside of the rock?  If this is a geode, would acidic liquids break it down (vinegar)?  I guess I can google that, too.  ;-)

Ramona

[Ramona]

Okie, I went on a search for Chalcedony geode and I DO think that is what this is.  On that assumption, I went ahead with removing some more of the matrix.  I believe a small amount of it remains, but these two pieces are now mostly cleaned.  I am really confused, now, though!  I am seeing what looks like some bryozoan fossil like lines on one of them?  Can there be fossils on the outer part of geods?  Here is the first piece, with what looks like lines to me.  The third images is the "inside" of what I think is the smaller part of a geode.  Will post more photos of the deeper piece now.

Ramona

[Ramona]

The second piece of what I think is Chalcedony geode, according to what was suggested to me.  (we do have geodes here in Alabama - I googled to make sure!).Two photos are of the outside and the last three are slightly different angles of the inside.  So, does this look like a geode?!  I think so, but would appreciate more expert opinions?

Thanks!!
Ramona

[ClearLake]

Yep, certainly looks like a geode to me. I dont know that I would call that an “expert” opinion, but I have collected and seen many geodes so take that for what it is worth. 

[Mark Kmiecik]

No obvious fossil/organic lines on the first one. Fossils are usually quite obvious, but when you're new to collecting it is a good idea to ask if you're not sure. You don't want to discard something important because you didn't see it. On the other hand you don't want to start reading in things that aren't truly there. There a lot of "structures" in the natural world that look like something else, optical illusions in a way. Sometimes heavy wear will make it nearly impossible to tell if something is of geological or organic nature. In those cases the only thing you can say is "maybe".

 

The second item is not so much a geode as it is a geode want-to-be. It got started on the road to becoming a geode, but was sidelined by another process before the geode forming was completed. That's why it's not as showy or well-formed as the images you see when you Google the word "geode". You should be aware that this happens quite frequently -- the interruption of processes -- and has happened millions of times in the past affecting all geological processes, thus giving us the splendid variety of mineral substances we have. (Or the nightmare of trying to identify them, if you look at it from that perspective.) That's what makes the game fun; otherwise we'd be bored after 5 minutes.

[Ramona]

46 minutes ago, Mark Kmiecik said:

No obvious fossil/organic lines on the first one. Fossils are usually quite obvious, but when you're new to collecting it is a good idea to ask if you're not sure. You don't want to discard something important because you didn't see it. On the other hand you don't want to start reading in things that aren't truly there. There a lot of "structures" in the natural world that look like something else, optical illusions in a way. Sometimes heavy wear will make it nearly impossible to tell if something is of geological or organic nature. In those cases the only thing you can say is "maybe".

 

The second item is not so much a geode as it is a geode want-to-be. It got started on the road to becoming a geode, but was sidelined by another process before the geode forming was completed. That's why it's not as showy or well-formed as the images you see when you Google the word "geode". You should be aware that this happens quite frequently -- the interruption of processes -- and has happened millions of times in the past affecting all geological processes, thus giving us the splendid variety of mineral substances we have. (Or the nightmare of trying to identify them, if you look at it from that perspective.) That's what makes the game fun; otherwise we'd be bored after 5 minutes.

Wow!  Thanks for this information!  This subject is definitely NOT boring, that is for sure!  I really appreciate all of the help and information I glean from this forum!

Ramona