We use cookies to show content based on your preferences. If you continue to browse you accept their use and installation. More information. >

FMF - Friends of Minerals Forum, discussion and message board
The place to share your mineralogical experiences

FMF English Forum is moderated by John S. White and Peter Megaw
 

Spanish message board






Newest topics and users posts
24 Apr-21:36:07 Re: chinese realgar (Rubytime)
24 Apr-16:56:48 Re: tourmaline included smokey quartz specimen real or fake? (Striker.Svr)
24 Apr-15:54:16 The mizunaka collection - rhodochrosite (Am Mizunaka)
24 Apr-14:30:17 Re: colourful crystals plus colourless crystals (Bob Carnein)
24 Apr-12:42:26 Re: colourful crystals plus colourless crystals (Bob Harman)
24 Apr-12:15:27 Re: colourful crystals plus colourless crystals (Bashka)
24 Apr-12:04:13 Colourful crystals plus colourless crystals (Bashka)
24 Apr-08:18:54 Re: help identifying this conglomerate (Joshtw)
23 Apr-18:44:42 Re: conglomerate but what type of minerals (Dale Hallmark)
23 Apr-18:25:36 Re: conglomerate but what type of minerals (Bob Harman)
23 Apr-18:14:48 Re: biotite?? not sure what this (James W)
23 Apr-18:13:40 Re: conglomerate but what type of minerals (James W)
23 Apr-18:12:39 Re: conglomerate but what type of minerals (James W)
23 Apr-18:11:54 Conglomerate but what type of minerals (James W)
23 Apr-18:10:24 Re: biotite?? not sure what this (Pete Modreski)
23 Apr-18:02:25 Re: biotite?? not sure what this (James W)
23 Apr-17:50:49 The mizunaka collection - rhodochrosite (Am Mizunaka)
23 Apr-17:37:48 Re: biotite?? not sure what this (Matt_zukowski)
23 Apr-17:27:14 Re: biotite?? not sure what this (James W)
23 Apr-17:11:40 Biotite?? not sure what this (James W)
23 Apr-12:00:06 Re: are there diamonds, peridot and sapphire in the igneous rocks? (Jesse Fisher)
23 Apr-11:45:28 Re: help identifying this conglomerate (Pete Modreski)
23 Apr-07:51:10 Re: help identifying this conglomerate (James)
23 Apr-07:08:37 Re: help identifying this conglomerate (Joe Weisberg)
23 Apr-07:07:55 Re: help identifying this conglomerate (Joe Weisberg)

For lists of newest topics and postings click here


RSS RSS

View unanswered posts

Why and how to register

Index Index
 FAQFAQ RegisterRegister  Log inLog in
 {Forgotten your password?}Forgotten your password?  

Like
42067


The time now is Apr 25, 2018 02:06

Search for a textSearch for a text   

A general guide for using the Forum with some rules and tips
What are these?
  
  Index -> FOR BEGINNERS: What is it? Where is it from?
Like


View previous topic :: View next topic  
Author Message

isreal




Joined: 05 Feb 2017
Posts: 6
Location: Nuevo Leon

View user's profile

Send private message

PostPosted: Apr 11, 2017 13:15    Post subject: What are these?  

Hello, I was walking in a mountain, in the dessert of Saltillo, Coahuila, Mexico, and I saw these rocks, they have almost perfect oval marks, I have more like these.
Why these marks, maybe they are fossils?

Thank you for your help.
it



4.jpg
 Description:
 Viewed:  1405 Time(s)

4.jpg



1.jpg
 Description:
 Viewed:  1403 Time(s)

1.jpg



2.jpg
 Description:
 Viewed:  1410 Time(s)

2.jpg



3.jpg
 Description:
 Viewed:  1406 Time(s)

3.jpg


Back to top
Reply to topic Reply with quote
Like
   

isreal




Joined: 05 Feb 2017
Posts: 6
Location: Nuevo Leon

View user's profile

Send private message

PostPosted: Apr 11, 2017 22:47    Post subject: Re: What are these?  

Maybe they are just simple stones? omeone can help me?
Back to top
Reply to topic Reply with quote
Like
   

Tobi




Joined: 07 Apr 2009
Posts: 2635
Location: Good Old Germany


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 12, 2017 02:16    Post subject: Re: What are these?  

isreal wrote:
Hello, I was walking in a mountain, in the dessert of Saltillo, Coahuila, Mexico, and I saw these rocks, they have almost perfect oval marks, I have more like these.
Why these marks, maybe they are fossils? Maybe they are just simple stones? omeone can help me?
I recommend you to read http://www.mineral-forum.com/message-board/viewtopic.php?p=19487#19487

But even without further information I'm sure they are not something special or precious. I have no knowledge about fossils, but I can tell you at least that they are no precious minerals, if this helps ;-)
Back to top
Reply to topic Reply with quote
Like
   

Pete Richards
Site Admin



Joined: 29 Dec 2008
Posts: 588
Location: Northeast Ohio


Access to the FMF Gallery title=

View user's profile

Send private message

PostPosted: Apr 12, 2017 09:11    Post subject: Re: What are these?  

They appear to be concretions or something similar. The middle shrank after the outer part became lithified, opening the cracks that can be seen on several pieces. These are not standard concretions, apparently, because typical concretions are flattened spheres (oblate spheroids), whereas these appear as if they were portions of cylindrical structures. They might be some sort of fossilized burrow.

While slightly more interesting than "simple stones", they are not particularly special, especially for a group like ours that focuses on minerals.

_________________
Collecting and studying crystals with interesting habits, twinning, and epitaxy
Back to top
Reply to topic Reply with quote
Like
   

isreal




Joined: 05 Feb 2017
Posts: 6
Location: Nuevo Leon

View user's profile

Send private message

PostPosted: Apr 18, 2017 14:22    Post subject: Re: What are these?  

Pete, thank you very much. I also think they are concretions or animal fossils. I also found these cristal calcites in the same place.

Regards!!
it



cuarzos.JPG
 Locality:
Coahuila (Coahuila de Zaragoza), Mexico
 Description:
 Viewed:  1070 Time(s)

cuarzos.JPG


Back to top
Reply to topic Reply with quote
Like
   
Display posts from previous:   
   Index -> FOR BEGINNERS: What is it? Where is it from?   All times are GMT - 5 Hours
Page 1 of 1
    

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


All pictures, text, design © Forum FMF 2006-2018


Powered by FMF