rock cycle t igneous pet ro lo g yLt what are the properties of igneous rocks and how do I identify themthe rock cycle is a never ending process of how the earthsmatter moves through the crustminerals aremade up of elementsfrom the periodictablerocks are made up of mineralsigneousrocks are formed by thecooling andcrystallizingofhot lava or magmatwo types of moltenrocklava not molten rock on the surface of earthmagma hot molten rock beneaththesurface of earthgrainsize is howbigor small an individualgraincrystal iswithin a rock these will be theminerals that make up therock look for colorstypesofgrainsmicroscopic cannot see with yournaked eye includesglassy vesicular glassylookingfine about the size of a sand partialcoarse larger than sand size particles 2mmlocationsintrusive formed cooled inside of the earth corse grainsextrusive formed cooled outside of the earth fine tomicroscopicgrainsmagma rockcolorslightcolored white pink clear tan grey and blackmediumcolored white grey green tan and blackdark colored dark grey green and blacklight colored magmatype felsicminerals within quartzfeldspars both micas bothhornblend rock names pumicerhyolitegranitemedium colored magmatype andesiticmineralswithin plagioclasefeldspar biotite mica hornblenderock names obsidian andesite dioritedark colored magmatype maficmineralswithin plagioclase feldspar olivine biotitemica hornblende usually a lotrock names scoria basalt gabbroIgneous RocksWeatheringtoooc efcompact andi ii imeltingf