- porphyroblastic
- por·phyro·blastic
English syllables. 2014.
English syllables. 2014.
porphyroblastic — adjective see porphyroblast … Useful english dictionary
Staurolite — is a red brown to black, mostly opaque, nesosilicate mineral with a white streak. It crystallizes in the monoclinic crystal system, has a Mohs hardness of 7 to 7.5 and a rather complex chemical formula: (Fe,Mg,Zn)2Al9(Si,Al)4O20(OH)4. Iron,… … Wikipedia
Porphyroblast — [ thumb|right|350px|An almandine garnet growing as a porphyroblast in a quartzitic gneiss. This particular garnet measures 3 cm. Location: Paraíba, Brazil.] A porphyroblast is a large mineral crystal in a metamorphic rock which has grown within… … Wikipedia
metamorphic rock — Any of a class of rocks that result from the alteration of preexisting rocks in response to changing geological conditions, including variations in temperature, pressure, and mechanical stress. The preexisting rocks may be igneous, sedimentary,… … Universalium