Can't download audible books to MP3 player - not happy, Jan. So I sprang the 50 bucks to buy a generic Dick Smith MP3 player because I thought - oh joy - I'd be able to carry my entire audible library around with me on a device that's as small as a matchbox. So I download some audible books. They're there on the device.
A common example of an extrusive igneous rock is basalt. Some extrusive rocks, such as obsidian and pumice, cool so rapidly that they completely lack crystal structure and are considered a volcanic glass. Pumice is just like obsidian except it is tiny shards of glass.
Because such slow cooling allows time for large crystals to form, intrusive igneous rock has relatively large mineral crystals that are easy to see. Granite is the most common intrusive igneous rock (Figure 4.12). Figure 4.12: A close-up of a granite sample.he holes make pumice so light that it actually floats in water. The most common extrusive igneous rock is basalt, a rock that is especially common below the oceans (Figure 4.15). Figure 4.13: Extrusive igneous rocks form after lava cools above the surface.