IS THIS A FOSSIL? ID HELP.

[Monika Kertowska]

Hello. I am a mineral collector living in Ireland and author of the blog collectingminerals.blogspot.com. A friend of mine, a German collector, recommended this website to me for fossil ID.
While being on a walk by Blackwater River in Mallow, Co. Cork, Ireland today, I found this stone that looks like a fossil. It was there among regular river pebbles, and it was the only one like this that I found.
On top it is rounded and covered with something that looks like the inside of a shell. The bottom also shows some of it, but is mostly a rock with visible layers. The whole thing just looks like a big, hand-sized oyster or mussel. Could you please help me identify if this is a fossil at all, and if so- what is it?
Any help greatly appreciated. Please, find pictures attached.
Monika

[Axinit]

Hello,

might indeed be an oyster - difficult to tell from the pictures. It would be helpful, if you could provide some info as to the geological setting - Ireland is a bit far away from continental Europe.

MINERALIENATLAS is a phantastic place to exchange/obtain information on minerals, rocks etc and fossil wood  .

The experts at Steinkern.de. are more likely to be able to answer your question - give it a try !

Good luck and best wishes

Harald

[Monika Kertowska]

Hello and thank you for your reply.
The area where I live is limestone, I find fossils quite often here (shells, corals). I`m a mineral collector but always take the fossils that I find for reference and sentimental reasons Also, I like to know what I have
I believe I`ll find someone here who will be able to tell me something about my stone.
Greetings,
Monika

[stoanklopfer]

Yes, seems to be the shell of an ostrea.

[harzgeist]

According to the geological map of Ireland the questioned object has been found in an area of Lower Carboniferous limestone.
Possibly a big brachiopod, like gigantoproductus ??
Can someone of the fossil-specialists (I'm not such!) confirm/deny this assumption ?

[giantcrystal]

Dear Monika

well, from the picture it can be a few things. It may be a type of big mussel.it may also be a type of stromatopore or it may be simply a waterworn piece of cave sinter with the typical stratification. Hard to tell from the photos

Anyway, I had a look to your wonderful blog about Irish Minerals. There are a few collectors here who have been to Ireland including myself. Do you know Barry Flannery ? He is always interested getting in touch with Irish mineral collectors. You can find his details on  http://www.irishminerals.com/page_1138054161250.html

Regards and Glück Auf

Thomas

[Monika Kertowska]

Hello everyone and thank you for your answers.
Could you please suggest if there is any way (method, test etc) in which I could find out what this is? I`m curious to know, really

Thomas, yes, I know Barry. There aren`t too many collectors here so we know one another and exchange info. What sites have you visited? Are you planning to come to Ireland again? Collecting folks always welcome Oh! And I`m glad you like my blog.

Monika

[giantcrystal]

Dear Monika

you can contact me at my website www.mineral-exploration.com, where you can also find a publication about Ireland (under Publications) Please email me and we can discuss mineral collecting in Ireland in more detail

Glück Auf

Thomas

[oliverOliver]

it may also be a type of stromatopore or it may be simply a waterworn piece of cave sinter with the typical stratification.

stromatopore or stromatolite was my first idea, too. But cave sinter would also be possible.