Strange flint fossil

[Thames Adventurer]

Hi!

 

I found this strange piece of flint on the Thames foreshore. Is this a fossil sea sponge?

 

Thank you

[Captcrunch227]

I'm not seeing a fossil here. I'm seeing a really cool rock though that mother nature carved into a very cool looking shape. 

[TqB]

Zooming in on the first photo, it is suggestive of a sponge. There's nothing that clearly indicates flint though (i.e. a broken surface, maybe with conchoidal fracture). It could also be a piece of weathered industrial slag which crops up there quite often - hard to tell from just photos.

[Thames Adventurer]

5 hours ago, TqB said:

Zooming in on the first photo, it is suggestive of a sponge. There's nothing that clearly indicates flint though (i.e. a broken surface, maybe with conchoidal fracture). It could also be a piece of weathered industrial slag which crops up there quite often - hard to tell from just photos.

 

Hmm, I think you could be onto something here with it being some sort a man-made material. Something just feels kind of "off" or weird about this piece; it's weighty and makes a sound like a flint, but it also appears kind of porous in places, rough in some whilst unusually shiny smooth in others. I don't think it's a metal though. If it is some sort of construction material, do you have any idea what it might be? 

[TqB]

1 hour ago, Thames Adventurer said:

 

Hmm, I think you could be onto something here with it being some sort a man-made material. Something just feels kind of "off" or weird about this piece; it's weighty and makes a sound like a flint, but it also appears kind of porous in places, rough in some whilst unusually shiny smooth in others. I don't think it's a metal though. If it is some sort of construction material, do you have any idea what it might be? 

Slag from metal extraction is essentially impure glass, with low metal content if the extraction has been efficient. (Older, historical slags tend to be heavier.) It often has gas bubbles and can be very similar in appearance to pumice but may be solid and glassy like obsidian, or a mixture.

Edited June 15, 2022 by TqB