What in the world?

[Becky Benfer]

Found in N central Ohio- it’s so oddly shaped and full of weird pieces. Maybe a conglomerate?? The bottom right area has a different, small dotted look. Could it consist of a fossil? Thanks for your help!

[Becky Benfer]

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[LabRatKing]

It is a cool looking bit of flowstone to my eyes. Id give it a nice vinegar bath and add it to my cool looking rocks collection.

[Becky Benfer]

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[Becky Benfer]

Pure vinegar? Or a diluted mixture?

[Becky Benfer]

I assume this is more flowstone as well?

[Becky Benfer]

[LabRatKing]

13 minutes ago, Becky Benfer said:

Pure vinegar? Or a diluted mixture?

I use dollar store distilled vinegar straight. It loosens up the dirt and such in about an hour., then a rinse and perhaps and old toothbrush and its a beaut!

 

If you aren't in a hurry dilute it by measuring out a cup and adding water to make a pint...this takes longer, but can sit overnight. (Don't do it with fossils though...it can damage them!)

[LabRatKing]

14 minutes ago, Becky Benfer said:

I assume this is more flowstone as well?

Yep.

 

Something fun you can do with cool rocks like this is use them to grow crystals. I used to mix up alum (or Borax) and water and drip it into the holes and let it dry. takes a few days/weeks and a couple of applications, but once you have a good layer of air-dried alum in there, then you can submerge the entire rock in an alum(or borax) supersaturated solution and in a week or so, you have cool crystals growing out of cool rocks. This kept my children very busy when they were young (and kept them out of my hair for a bit!) They spent hours experimenting with food coloring to grow brightly colored crystals. 

 

Not quite fossil prepping, but its a good time killer for these stay at home times!

[Mark Kmiecik]

FYI for anyone interested.

Vinegar is normally less than 10% acetic acid in solution, usually in the 5 to 8 percent range. It is already diluted. Even though it is considered a "weak" acid, if you got some 100% acetic acid in your mouth you would be very unhappy. It's what gives ketchup its bite. Diluting an acid does not make it weaker. It only slows down the reaction by limiting the surface area exposed to acid molecules at the same time. In other words, the acid molecules have to "compete" with the water molecules to contact the surface, so with dilution a lesser quantity of acid molecules can physically contact the surface simultaneously. Dilution also prevents the reaction from becoming violent (explosion in some cases).

[erose]

On 11/19/2020 at 6:47 PM, LabRatKing said:

I use dollar store distilled vinegar straight. It loosens up the dirt and such in about an hour., then a rinse and perhaps and old toothbrush and its a beaut!

 

If you aren't in a hurry dilute it by measuring out a cup and adding water to make a pint...this takes longer, but can sit overnight. (Don't do it with fossils though...it can damage them!)

An hour? Yikes! If the fossil is preserved as calcite you can literally dissolve it away.  If you are trying this for the first time I would suggest setting a timer for 15-20 minutes at the most and check it before going longer.  

 

Acids, even simple vinegar, have very specific uses.  What works well on silicated fossils might destroy a calcitic specimen. And some acids are just extremely dangerous.

 

Do a search here on the forum for cleaning with acids and read, read, read.  

[LabRatKing]

22 hours ago, Mark Kmiecik said:

FYI for anyone interested.

Vinegar is normally less than 10% acetic acid in solution, usually in the 5 to 8 percent range. It is already diluted. Even though it is considered a "weak" acid, if you got some 100% acetic acid in your mouth you would be very unhappy. It's what gives ketchup its bite. Diluting an acid does not make it weaker. It only slows down the reaction by limiting the surface area exposed to acid molecules at the same time. In other words, the acid molecules have to "compete" with the water molecules to contact the surface, so with dilution a lesser quantity of acid molecules can physically contact the surface simultaneously. Dilution also prevents the reaction from becoming violent (explosion in some cases).

Yes. Though generally even distilled vinegar is less than that usually in the 5-7% range. Glacial Acetic Acid (>95%) is not readily available to consumers. There is no risk of thermoreactions with acetic acid and water. (Don't mix it with nitric however.)

6 hours ago, erose said:

An hour? Yikes! If the fossil is preserved as calcite you can literally dissolve it away.  If you are trying this for the first time I would suggest setting a timer for 15-20 minutes at the most and check it before going longer.  

 

Acids, even simple vinegar, have very specific uses.  What works well on silicated fossils might destroy a calcitic specimen. And some acids are just extremely dangerous.

 

Do a search here on the forum for cleaning with acids and read, read, read.  

For a non-fossiliferous quartzite like this one, there is no harm whatsoever in using vinegar.

[Rockwood]

I'm thinking this looks more like mudstone that iron carbonate concretion has weathered out from.

[erose]

20 hours ago, LabRatKing said:

For a non-fossiliferous quartzite like this one, there is no harm whatsoever in using vinegar.

 

We always need to make sure the new folks understand the limitations. I would have just suggested a really good soak in soap and water to start.

 

[Becky Benfer]

I’m having a hard time getting the green  “gunk” off some of the rocks. Sometimes vinegar makes them fizz and I panic!  But soaking doesn’t help much so then I scrub because I lose patience.

[Rockwood]

45 minutes ago, Becky Benfer said:

I’m having a hard time getting the green  “gunk” off some of the rocks.

Medicine cabinet hydrogen peroxide should help clean off dried on modern algae.