Help for my thesis

[LuisODL]

Hi, I come here because I need some help. I just collected samples for my thesis and I´ve just realized that my samples are sandstones with many mollusca fossils.

 

My problem here is that, I dont know how to extract the fossils without destroying them. Please help me, I need this so much, and I cant find anything about dissolving sandstones.

 

Greetings From Monterrey, México.

Edited August 29, 2017 by LuisODL

[Miocene_Mason]

These look like gastropods, and unfortunately I don't think that you can safely take these out, safer leaving them in situ and looking for some that have eroded in a more favorable manor.

Welcome to the forum by the way!

[FossilDAWG]

I am not aware of any methods that are routinely used to "dissolve" sandstones.  Do you know anything about the minerology of your material, i.e. what the cementing mineral is?  Perhaps some of the approaches that are used to disaggregate shales could be useful, such as quaternary ammonium detergents.  Years ago there was a product called Quaternary O that was great for cleaning off some types of shale (depending on the minerology), but it has not been sold for many years and I don't know of a similar product that is commercially available.

 

Don

[Ptychodus04]

You could try the method outlined in the paper attached. I have not personally employed any chemical preparation technique for sandstone matrices. I lean towards mechanical preparation when at all possible.

Triplehorn_2002_Journal-of-Paleontology.pdf

[Al Dente]

Hydrofluoric acid will dissolve quartz sand but is extremely dangerous. I wouldn't get near the stuff but it is used in some fossil labs.

[LuisODL]

25 minutes ago, WhodamanHD said:

These look like gastropods, and unfortunately I don't think that you can safely take these out, safer leaving them in situ and looking for some that have eroded in a more favorable manor.

Welcome to the forum by the way!

Hi WhodamanHD, thanks for answering me, yeah, I found some gastropods too, but pictures like this with bivalves and ammonites are too big to upload, and Im just allowed to upload 3.95mb or less. If you could give me your e-mail to send you some more pics Ill be glad.

Thanks and greeting from Monterrey, México.

[jpc]

I would also stay away form hyrdoflouric.  It is nasty stuff.  Dissolves glass. 

[LuisODL]

33 minutes ago, FossilDAWG said:

I am not aware of any methods that are routinely used to "dissolve" sandstones.  Do you know anything about the minerology of your material, i.e. what the cementing mineral is?  Perhaps some of the approaches that are used to disaggregate shales could be useful, such as quaternary ammonium detergents.  Years ago there was a product called Quaternary O that was great for cleaning off some types of shale (depending on the minerology), but it has not been sold for many years and I don't know of a similar product that is commercially available.

 

Don

Hi FossilDAWG, Thanks for replying my post, Ill take a look about mineralogy and Ill post it here. And thanks about the "Quaternary O" info, Ill take a look for a similar product.

Greetings From Monterrey, México.

1 minute ago, jpc said:

I would also stay away form hyrdoflouric.  It is nasty stuff.  Dissolves glass. 

Thanks for the info, I dont want to know what it would do with me haha

[LuisODL]

36 minutes ago, Ptychodus04 said:

You could try the method outlined in the paper attached. I have not personally employed any chemical preparation technique for sandstone matrices. I lean towards mechanical preparation when at all possible.

Triplehorn_2002_Journal-of-Paleontology.pdf

Hi Ptychodus04, Thanks for replying. Wow, that paper its just what i needed. Ill take a look and Ill let you know how it goes. Thanks a lot and greetings from México.

30 minutes ago, Al Dente said:

Hydrofluoric acid will dissolve quartz sand but is extremely dangerous. I wouldn't get near the stuff but it is used in some fossil labs.

Hi Al Dente, thanks for replying. Its good to know how dangerous it is. Thanks a lot and Greetings from Mpnterrey México.

[JohnBrewer]

2 hours ago, Al Dente said:

Hydrofluoric acid will dissolve quartz sand but is extremely dangerous. I wouldn't get near the stuff but it is used in some fossil labs.

I would advise against hydroflouric acid. It's probably the most dangerous of all acids. It's so dangerous that on uk safety data sheets it should only be used with someone else present. If you get it on your skin you won't initially feel it and it will rapidly de-calcify bone. Google hydroflouric acid images....

[Fruitbat]

One OTHER thing to consider as far as hydrofluoric acid is concerned is the effect that it will have on the fossils themselves!  I have used the stuff when I was teaching college-level chemistry and, to be honest, I avoid it like the PLAGUE!  VERY nasty stuff!

 

-Joe