Has anyone used sodium hexametaphosphate to disolve clay deposits?

[Manticocerasman]

I recently aquired a whole bunch of clay containing small fossils, but the clay is extreemly hard and I have trouble to extract the fossil by sieving this with water.

For now I am drying the clay and putting it in sieves and rincing it with watter, but it is extremely labour intensive and uses lots of water and the result is not realy good.

 

Someone that collects minerals recomended me Sodium hexametaphosphate to help disolving the clay, but I have no experience whatsoever with this product, so like the titel of the post sugests  ; Has anyone used sodium hexametaphosphate to disolve clay deposits?

I'am of course also open to other alternatives to extract residu from clay  

 

 

thx,

Kevin

[oilshale]

Might help a bit:

A review of the laboratory preparation of palynomorphs with a description of an effective non-acid technique

A_review_of_the_laboratory_preparation_of_palynomo.pdf

[digit]

Drying out the clay (to induce cracking) and re-wetting does seem to aid in water penetration and help break down the clay. I've used this for sticky micro-matrix at the Shark Tooth Hill site in California. Sodium hexametaphosphate (known by the brand name Calgon water softener) has been used successfully in the breakdown of clay--we have bottles of it at the screen washing station at the FLMNH. If you can find it from a scientific supply store or off the shelf (assuming Calgon is for sale in Belgium) I'd certainly suggest giving it a go.

 

 

https://en.wikipedia.org/wiki/Calgon

 

 

Cheers.

 

-Ken

[pachy-pleuro-whatnot-odon]

I believe @mamlambo has worked with this as well, and, if memory serves me right, has even made a video about it. Unfortunately, I haven't been able to find it back...

[Manticocerasman]

Thank you all for the replies, I just struggle to find a suplier in belgium.

"Calgon" exists here as a brand, but I dont know if it is the same product.

 

 

[digit]

Sounds like a trip to the store and some studying of ingredients labels is in your future.

 

 

Let us know how it works out (assuming you get your hands on some and experiment).

 

 

Cheers.

 

-Ken

[jpc]

another option I have used successfully is any of the citrus based industrial cleaners.  I use it at about 1/4 mixture with water after doing an intitial screen washing with just water and letting it dry.  And it smells good. 

 

[Coco]

To extract fossils from clay I use diluted hydrogen peroxide. I soak, it defloculates the clay, I sift and I dry. I repeat if necessary, taking care to thoroughly dry the sediment before starting again.

 

Coco

[Manticocerasman]

I just got the stuff. I’ll have a try this weekend

[MarcoSr]

Before I try any chemicals, I dry the clay really well (can dry in oven at 150 F) and then put it in 5 gallon buckets.  I add the hotest tap water (or boiling water) to the buckets and let it sit overnight.  This works for me on most clays that I work with.  Sometimes several cycles of drying and hot water are required.  If this doesn't work I add a laundry detergent to the buckets with the hot water that works on heavy dirt/clay stains.  I don't like doing this because you can get a lot of suds when washing the mixture in a sieve afterwards.

 

Edit:  Before using any chemicals on your matrix you should try what you want to use on a small sample.  First this will show you if the chemicals will break the matrix down and secondly that they won't damage or dissolve the fossils you want to find.  You have to be really careful with what chemicals you choose if you are looking for carbonate based fossils especially.  In addition some chemicals can have very adverse reactions with other things in the matrix like pyrite for example.  I can't use Hydrogen Peroxide on several of my matrixes because it reacts with the pyrite and etches and turns blue the tooth enamel.

 

Marco Sr.

[Manticocerasman]

Here goes the first test. I just used a little clay straight out of the bucket.

I aded a little of the powder and then aded water. 
I’ll wait a couple of days and check the results.

after that I’ll see what other steps I need to make. 
the idéal I think would have been to dry the clay before doing this, but the weather here is terrible for now and the humidity in the air is to high to let something dry.

 

[caterpillar]

39 minutes ago, Manticocerasman said:

the humidity in the air is to high to let something dry.

 

You can use your kitchen oven

[Manticocerasman]

It seem to have worked, the clay was reduced to a stikky mud.

I then used  large bassin with 2 sieves on top. 
I poured ( and pushed) themud and watter in the sieves.

I then added water so that everything was submerged and started sieving.

there are still a few pieces of clay, but most has washed of. 
the to sieves ar now on top of the bassin to dry. 

[digit]

Looking good.

 

 

Cheers.

 

=Ken