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Updated Friday 29th September 2006

Step by step rock analyser will help you identify your sample

What rocks are these? Copyrighted image Icon Copyright: OU

You have identified your rock as having a crystaline structure.
You have told us your sample has a random crystaline structure: This means your rock is an igneous rock.
You have reported your sample has a crystal structure of medium-sized granules.
Is this correct? If not, start again or go back a step.

Thinking now about the colour of your rock:

If the colour is light, we have identified your sample as microgranite

If the rock is of an intermediate colour, we believe your rock to be microdiorite

If your sample is dark, we can identify your rock as micrograbbo

More help with this question:
Rocks come in a multitude of colours, for simplicity we have divided them into three catgories:

Dark coloured rocks: may be black, dark brown, dark grey or dark green.

Intermediate coloured rocks: are pale grey, reddish brown or green.

Light coloured rocks: are pale pink, pale green, light grey or white.

Tip: the colour of a rock can also be influenced by its grain size. Very fine grained rocks often appear much darker than their coarse grained or coarsely crystalline equivalents.

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For further information, take a look at our frequently asked questions which may give you the support you need.

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