quartz porphyry

noun

Definition of quartz porphyry

: a porphyritic extrusive or dike rock in which quartz with more or less corroded crystals and orthoclase and usually mica, amphibole, or pyroxene occur as phenocrysts in a groundmass that is felsophyric, granophyric, or vitrophyric

There's more!

Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!
Already a subscriber? Log in.

Seen and Heard

What made you want to look up quartz porphyry? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

of very fine texture or delicate form

Get Word of the Day daily email!

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!