Just like baking cookies, metamorphic rocks need to be "cooked" just right!
Click on image for full size
Windows to the Universe original image

How Much Do Metamorphic Rocks Change?

Sometimes rocks are metamorphosed just a little bit.

Sometimes rocks are changed a lot.

It depends on how much the rocks are affected by heat and pressure.

Rocks that are metamorphosed just a little bit, form within the Earth at temperatures a little hotter than the oven temperature needed to bake chocolate chip cookies. Metamorphic rocks are greatly changed when they form in conditions about four times hotter than the baking oven. At that temperature, the rocks almost melt!


Last modified June 20, 2003 by Lisa Gardiner.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

What’s That Mineral?

Spotting minerals is fun! There are many different types of minerals. Each has a different name and special traits. You can learn more about minerals by looking closely at them to understand their special...more

Quartz

This mineral is called quartz! Sometimes it looks white like milk but usually it looks clear like glass, sometimes with a little pink or gray tinge of color. You can find crystals of quartz in many different...more

Mica Minerals

Mica minerals make some rocks sparkle! Look for them in your igneous and metamorphic rocks. Do they make your rocks sparkle? They break into flat plates because they have cleavage. ...more

Feldspar

This is a feldspar mineral! Look for it in igneous rocks where it looks like white or pink crystals. You might find it in other types of rocks as well. ...more

Olivine

The mineral that is green is called olivine! Look for it in igneous and metamorphic rocks. In this picture, olivine is filling a hole in the igneous rock. ...more

Type of Minerals

There are at least 2000 minerals on Earth. That's a lot of minerals! But you don't need to know all of them to spot the minerals lurking in the rocks of your backyard. That is because only a small number...more

What Is a Mineral?

Minerals are the building blocks of rocks. There are many different types of minerals. All of them are solid and all are made of atoms of elements. Minerals can grow even though they are not alive. Most...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA