I tried to look for any similar rocks on the Internet but couldn't find anything and I don't know much about geology.

I've been given this rock when I was a child and now I'm just curious to know what it is.

To me it looks like a rock around a rock, I don't know maybe lava of some sort ended up around a regular rock and that's the result.

If you could enlight me id really appreciate

Regarding its properties

The inside rock (from now on that's how I'll call the white part inside) is white, milky and not transparent.

The outside rock (the black part around) is grey, almost a metallic color. The border are darker almost black you see it clearly on the second picture.

You can see my hand as a scale it is approximately 6/7 cm long and 2/3cm thick.

Weight is normal to me but again I'm not a specialist.

I have no idea where it was found, the only info its original owner gave me was that he called it an "enrobé" (I'm French and that's a French word which means that something is around another thing)

Regarding its hardness, I don't want to break it but my fingernail definitely not scratch it.

It doesn't smell anything.

Also there is a brown stain (see picture 2) but I don't know if it's natural or not. It looks like it has nothing to do here.

enter image description here

enter image description here

enter image description here

  • $\begingroup$ Welcome to earth science stack exchange. Please see this guide on asking rock identification questions and be sure to update your post with necessary information and keep an eye on the comments so you can provide needed information as necessary. $\endgroup$ – casey Jan 30 '16 at 22:18
  • $\begingroup$ Will do thanks for the guide imma check it out now $\endgroup$ – Raph Petrini Jan 30 '16 at 22:19
  • 2
    $\begingroup$ Looks more like a delicious cookie to me than a rock. How does it taste? $\endgroup$ – Wolfgang Bangerth Jan 31 '16 at 17:57
  • $\begingroup$ Haha tastes like a rock, definitely not a cookie but maybe you're on the right track. 2000 years old fossil cookie ^^ $\endgroup$ – Raph Petrini Jan 31 '16 at 17:59
  • $\begingroup$ looks like a marble and also looks like a potato $\endgroup$ – Always Confused Aug 9 '16 at 15:08

Your rock looks like a piece of light grey colored basalt with chalcedony vein running through it. I've collected pieces very similar last summer along the Bay of Fundy near Scot's Bay, NS

enter image description here enter image description here enter image description here

  • $\begingroup$ Thanks for your answer. Any way you can post some pictures of your pieces so I can compare with mine and confirm that's what it is. $\endgroup$ – Raph Petrini Mar 29 '16 at 7:52

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.