I found a rock on a beach in north-east Evia, Greece. Half is light gray, and half is dark gray. There are white (or very light gray) thin lines that form swirls throughout, crossing the light/dark gray boundary in the main body of the rock. To me, they look like fossilized leaves or something similar.

What is the best way to work out what this is? There seems to be an abundance of different rock types, many colors, but there are many similar stones to this one, all worn into smooth rounded pebbles.

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    $\begingroup$ Good photographs with a scale bar would be useful... $\endgroup$
    – winwaed
    Apr 20, 2014 at 16:29
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    $\begingroup$ also measurements of relative hardness would help. $\endgroup$
    – Neo
    Apr 20, 2014 at 16:40
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    $\begingroup$ See meta.earthscience.stackexchange.com/questions/124/… $\endgroup$
    – naught101
    Apr 23, 2014 at 0:13
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    $\begingroup$ The question is about what methods a non-geologist can use to identify a rock, not about a particular specimen. (Read the second half of the question.) $\endgroup$
    – user2821
    Jan 18, 2017 at 6:50
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    $\begingroup$ @Tbb thanks yes that was the question, but I might use naught101's link to check my answer, thanks for the tips all :) $\endgroup$ Jan 18, 2017 at 8:05

1 Answer 1


OK, so you've found yourself an interesting rock and you want to know how to identify it. I am going to go ahead and assume that you haven't studied Geology before (apologies if that's an assumption too far).

The first thing you can do is to head to your local public library and find a basic "rocks, minerals and fossils" identification book, and try to match up what you have with something in the book. Most of these books will include some kind of description of the various tests you can do (Mohs Hardness Tests, Acid Tests, Flame tests etc).

A quick google search for the geology of the area in which you found the rock might also give you a good starting point. You are more than likely not going to find an exact match by doing this, but it will help later if you have some idea of what you might have. It also means that you will have to look at the rock critically and you'll gain far more for having tried to identify it yourself. (I work with helping ID fossils on a regular basis, and it's far more rewarding if the person who has found the fossil has some idea as to what they have, or at least a reason for their identification).

If that doesn't get you anywhere, you can turn to the internet, there are places such as the NHM's Nature Plus where you'll find other people including experts and amateur rock hounds who might be able to give you more help. You will want to have good photographs with a scale (coins, Lens Cap, Rulers all apply).

If all else fails, Head to your local museum with a geological collection and look at the collection. You can also ask to speak to a geological curator and they should be able to help you identify your specimen (as your profile lists London as your location, the Natural History Museum's Angela Marmot Centre, The Horniman Museum, or British Geological Survey are all good bets).

  • $\begingroup$ This is a great answer, thanks! Nice to find this after nearly 3 years when I forgot I had asked it, apologies for leaving it so long to respond. $\endgroup$ Jan 18, 2017 at 8:10

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