Q&A for How to Identify Igneous Rocks

Return to Full Article

Coming soon

Add New Question

Question

Is a smooth black stone I found on an old construction site likely to be an obsidian?

Community Answer

It could be, it depends on your location. If the rock has a glass-like texture or if you can see rings in it, it is very likely to be obsidian.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 25 Helpful 85
Question

How do I differentiate between granite and diorite?

Community Answer

Granite is a felsic intrusive rock and always has a red to pink or orange hue to it depending on how much K-spar it contains. Diorite is an intermediate intrusive rock which has a salt and pepper appearance.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 34 Helpful 67
Question

How many layers does an igneous rock have?

Community Answer

The common igneous rock (not including obsidian) has between 8 and 13 layers.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 29 Helpful 67
Question

Who can I find to identify my rocks?

Community Answer

Contact the geology department of a college in your area, or search the Internet for options. Someone may be able to identify your rocks based on images and your descriptions.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 31 Helpful 49
Question

Where can I find them?

Community Answer

You can mainly find them in mountains and at high altitudes but anywhere there is open land is a good place to start.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 25 Helpful 34
Question

Can I find igneous rocks in or near extinct volcanoes?

Community Answer

That depends on your luck, but theoretically you should be able to.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 21 Helpful 20
Question

How can I decide whether or not an igneous rock formed from a volcanic eruption?

Community Answer

Extrusive igneous rock (that was formed after being erupted from a volcano) will have a much smaller crystal size than an intrusive igneous rock.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 24 Helpful 18
Question

How can I send a picture of my rock?

Community Answer

You can send the picture via e-mail, text, social media platforms, or find a website that will allow you to send images.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 26 Helpful 23
Question

I found a rock that has features of both metamorphic and igneous rock. Which one is it?

Community Answer

It depends on which specific features it has. For example, if it has parallel crystals, it's metamorphic.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 17 Helpful 10
Question

What is a rock that is black with red marble and layers of white?

Community Answer

It is a metamorphic rock. If you can visibly see different colored lines, that means it is foliated.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 11 Helpful 18
Question

How would I classify a goose egg river rock?

Community Answer

Depending on the characteristics of the rock, you could classify it as either igneous or sedimentary.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 0 Helpful 0
Question

If there are crystals present, how do I know if the rock is igneous or metamorphic since both types can have crystals?

Community Answer

Igneous rocks will have the crystals spread all around the rock, while metamorphic rocks have layers of crystals that are all the same size.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 0 Helpful 0
Question

What are the mineral compositions of basalt?

Community Answer

Basalt is a dark-colored, fine-grained igneous rock composed mainly of plagioclase and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 1 Helpful 0
Question

How do I tell what type of rock I have?

Community Answer

Look at the rock closely. See if it has layers or crystals. Look at the grain patterns and the grain in general. Use a rock identification book or chart to help you.

Thanks! We're glad this was helpful.
Thank you for your feedback.
If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
Yes No

Not Helpful 0 Helpful 1