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.
It is widely used for architectural construction, ornamental stone and monuments. PUMICE: An igneous-volcanic rock, it is a porous, brittle variety of rhyolite and is light enough to float. It is formed when magma of granite composition erupts at the earths surface or intrudes the crust at shallow depths.