All Words Glossary

Glossary of Petrography - Rocks, Minerals Terms
beginning with letter P
Browse the Petrography - Rocks, Minerals Glossary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

pebble Tweet Definition of pebble Like Definition of pebble on Facebook
noun
  1. A small stone
  2. (geology) A rock fragment between 4 and 64 millimetres in diameter (especially a naturally rounded one)
  3. (curling) A small droplet of water intentionally sprayed on the ice that cause irregularities on the surface.
verbto pebble
  1. To pave with pebbles.
  2. (curling) To deposit water droplets on the ice. e.g. to pebble the ice between games.
pegmatite Tweet Definition of pegmatite Like Definition of pegmatite on Facebook
noun
  1. A coarsely crystalline igneous or plutonic rock composed primarily of feldspar and quartz, normally with muscovite and/or biotite mica. Often contains other minerals, which may be of economic importance. Pegmatite is chemically identical to granite, but has a much coarser crystal structure. Common colors are gray, white, and pink. Pegmatite is quarried for decorative stone and as a source of beryllium, columbium and tantalum when these are present. Gemstones of the quartz/silicate family may also be found in pegmatites.
peridotite Tweet Definition of peridotite Like Definition of peridotite on Facebook
noun
  1. (mineralogy) a rock consisting of small crystals of olivine, pyroxene and hornblende; the major constituent of the Earth's mantle
petrography Tweet Definition of petrography Like Definition of petrography on Facebook
noun
  1. (geology) the description and classification of rocks
phenocryst Tweet Definition of phenocryst Like Definition of phenocryst on Facebook
noun
  1. (mineralogy) any relatively large crystal embedded in a more fine-grained or glassy igneous rock
phonolite Tweet Definition of phonolite Like Definition of phonolite on Facebook
noun
  1. (mineralogy) a light-coloured rock of volcanic origin composed mostly of alkali feldspars
phosphorite Tweet Definition of phosphorite Like Definition of phosphorite on Facebook
noun
  1. (mineralogy) a sedimentary rock rich in phosphate minerals such as apatite
phyllite Tweet Definition of phyllite Like Definition of phyllite on Facebook
noun
  1. (geology) a type of metamorphic rock formed from clay-rich sediments called pelites
pitchstone Tweet Definition of pitchstone Like Definition of pitchstone on Facebook
noun
  1. (geology) a natural glass, that is rich in microscopic crystalites, formed by the rapid cooling of lava or magma
pore Tweet Definition of pore Like Definition of pore on Facebook
noun
  1. a tiny opening in the skin
  2. by extension any small opening or interstice, especially one of many or allowing passage of a fluid.
verb (por, ing)
  1. to study meticulously; to go over again and again.
  2. to meditate or reflect in a steady way.
porphyritic Tweet Definition of porphyritic Like Definition of porphyritic on Facebook
adjective
  1. of or pertaining to porphyry
  1. (geology) containing large crystals in a fine mass of material
porphyry Tweet Definition of porphyry Like Definition of porphyry on Facebook
noun (wikipedia, porphyry (geology))
(
porphyr, ies)
  1. (geology) a hard igneous rock consisting of large crystals in a fine-grained matrix
pumice Tweet Definition of pumice Like Definition of pumice on Facebook
noun
  1. A light, porous type of pyroclastic igneous rock, formed during explosive volcanic eruptions when liquid lava is ejected into the air as a froth containing masses of gas bubbles. As the lava solidifies, the bubbles are frozen into the rock.
pyroxenite Tweet Definition of pyroxenite Like Definition of pyroxenite on Facebook
noun
  1. (geology) A heavy, dark igneous rock consisting mostly of pyroxene minerals with smaller amounts of olivine and hornblende.

Browse the Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 Find:
  Words Starting With:
  Words Ending With:
  Words Containing:
  Words That Match:

 
Translate Into:
Dutch   French   German
  
Italian   Spanish
    Show results per page.

   
Allwords Copyright 1998-2019 All rights reserved.