There are approximately 1.5 gallons of blood in an average human body. Average adult has 6 liters of blood (just under 1 and a half gallons), the average child has 1.5 liters, and the average infant has 500 mL of blood. Source(s): I'm a biology major.
Muscovite is another common mica mineral that has a single perfect cleavage similar to biotite and phlogopite. It also occurs in the same igneous and metamorphic rocks that biotite is found in. However, muscovite is much lighter in color than biotite, typically being colorless to white.
Examples of intrusive igneous rocks are diorite, gabbro, granite, pegmatite, and peridotite. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. Some cool so quickly that they form an amorphous glass. These rocks include andesite, basalt, obsidian, pumice, rhyolite, scoria, and tuff. Pictures and brief descriptions of some common igneous rock types are shown on this page. Diorite is a coarse-grained, intrusive igneous rock that contains a mixture of feldspar, pyroxene, hornblende, and sometimes quartz.