Fragile Porifera

[fossilizator]

Hello from Baltic Sea! In Svetlogorsk only one find this time. This is Porifera, i think. I don't know the age yet. Found her among the ferruginous sand. It is a sponge, but very fragile. By how did she survive all this time? Especially after falling off a slope...

Inside, they have an interesting layered structure.

The place of the find is marked with gloves. She fell from about 7 meters.

[fossilizator]

After cleaning. How fix it so that it is not so fragile. Anyone, please advise something.

Top:

Inside

Behind:

[Tidgy's Dad]

Looks more like a coral to me.

Perhaps something from the family Oculinidae akin to Astrhelia ? 

Nice find. 

[Thomas.Dodson]

Nice find. Regarding the fragility a consolidant like Paraloid B-72 or something similar will help. It's a clear resin that you form a solution with acetone and coat/soak the fossils. When the acetone evaporates it leaves the resin permeated in the specimen providing structural reinforcement.

[digit]

Nope. Not a coral but a remarkably preserved sponge. I'm quite amazed!

 

Corals might also have a layered structure which is what I think Adam noticed. If you look on the surface you will not see evidence of uniformly spaced corallite structure but instead you will see  many incurrent pores (ostia) and several larger outcurrent pores (oscula).

 

A consolidant like B-72 as mentioned above would be one of the better ways to consolidate this delicate find. It can usually be found in plastic bead form from online retailers. Search for the terms "paraloid" or "B-72" and "consolidant" and you might be able to locate some. Dissolve the plastic bits in acetone to make the working consolidant and dip your sponge into the solution and set it out to dry after draining well. Most porous fossils will soak up the consolidant like a sponge--your fossil has a head start. If you find B-72 difficult to obtain you can use a low-tech substitute of white glue (the simple glue often used in school projects when you were a kid) diluted in a 10:1 ratio with water. The water won't evaporate as well as acetone so you'd have to be extremely careful if you chose to use this substitute as you wouldn't want to be letting any of the consolidant pool up or plug up any of the fine detail. With this type of detailed find I'd make the effort to obtain the B-72. Also, be careful with acetone and only use it outdoors with good ventilation.

 

A sponge fossil this well preserved is not common and I'd suggest entering it in the Fossil Of The Month contest.

 

 

Cheers.

 

-Ken

[fossilizator]

40 minutes ago, digit said:

A consolidant like B-72 as mentioned above would be one of the better ways to consolidate this delicate find. It can usually be found in plastic bead form from online retailers. Search for the terms "paraloid" or "B-72" and "consolidant" and you might be able to locate some. Dissolve the plastic bits in acetone to make the working consolidant and dip your sponge into the solution and set it out to dry after draining well. Most porous fossils will soak up the consolidant like a sponge--your fossil has a head start. If you find B-72 difficult to obtain you can use a low-tech substitute of white glue (the simple glue often used in school projects when you were a kid) diluted in a 10:1 ratio with water. The water won't evaporate as well as acetone so you'd have to be extremely careful if you chose to use this substitute as you wouldn't want to be letting any of the consolidant pool up or plug up any of the fine detail. With this type of detailed find I'd make the effort to obtain the B-72. Also, be careful with acetone and only use it outdoors with good ventilation.

 

2 hours ago, Thomas.Dodson said:

Nice find. Regarding the fragility a consolidant like Paraloid B-72 or something similar will help. It's a clear resin that you form a solution with acetone and coat/soak the fossils. When the acetone evaporates it leaves the resin permeated in the specimen providing structural reinforcement.

Yes. Our museum restorer said we have a paraloid B-72. She will prepare a solution with acetone. I'll show you what happens.

44 minutes ago, digit said:

A sponge fossil this well preserved is not common and I'd suggest entering it in the Fossil Of The Month contest.

Wow! I will try!

[digit]

8 minutes ago, fossilizator said:

Yes. Our museum restorer said we have a paraloid B-72. She will prepare a solution with acetone. I'll show you what happens.

Fantastic! This will be the best way of preserving that specimen.

 

If I were you I think I'd go back to that site and see if this sponge was a unique find or if there are others hiding there.

 

 

Cheers.

 

-Ken

[DPS Ammonite]

It looks like Paleogene and Neogene rocks are nearby.

Here is a reference with a detailed map of the area in Russian. Maybe it mentions the fossil too. Maybe someone can help translate.

https://www.researchgate.net/profile/Algimantas_Grigelis/publication/273870420_Stratigraphy_of_Paleogene_deposits_of_the_Baltic_area_Izvestiya_Akademii_nauk_USSR_ser_geol_Moscow_1971_Rus_self-arch/links/550ef6910cf21287416afc54/Stratigraphy-of-Paleogene-deposits-of-the-Baltic-area-Izvestiya-Akademii-nauk-USSR-ser-geol-Moscow-1971-Rus-self-arch.pdf?origin=publication_detail

 

I looks like a sponge with some intergrown coral. It sort of reminds me of how the sponges and corals grow together in the Devonian Martin Formation of Arizona.
 

Does this close up look like coral to everyone?

Edited December 10, 2020 by DPS Ammonite

[oyo]

Yes, it´s a coral + a briozoan.

Culicia parasitica (coral) + Celleporaria (briozoan)

[digit]

On 12/10/2020 at 2:52 PM, DPS Ammonite said:

Does this close up look like coral to everyone?

I do have to admit that looking closer at these circular features, they do seem to have the remnants of septa that sponges (at least modern ones) would never have.

 

I do believe @oyo has hit the nail on the head.

 

https://www.researchgate.net/publication/226544620_Le_genre_Culicia_Scleractiniaire_systematique_ecologie_et_biogeographie_au_Cenozoique/figures?lo=1

 

I do love to learn new things here on the forum.

 

 

Cheers.

 

-Ken

[digit]

On 12/10/2020 at 4:59 AM, Tidgy's Dad said:

Looks more like a coral to me.

And Adam wasn't fooled either.

 

 

Cheers.

 

-Ken

[fossilizator]

Yesterday I returned to the slope and unfortunately did not find anything. digit thank you for link. So, this is bryozoan with parasitic coral. Awesome!

Is the layered structure a sign of bryozoan growth? How are stromatolites?

 

p.s. how i can do link like this?

@oyo