from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Being or pertaining to a crystal-lined irregular cavity or vug most commonly found in granitic pegmatites.
from The Century Dictionary and Cyclopedia
- A word introduced by Rosenbusch to designate the structure of rocks of the granitic family, where the magma in assuming a crystalline character has shrunk in dimensions so as to leave numerous small cavities, giving the mass a structure somewhat analogous to that commonly designated as saccharoidal, as in the case of metamorphic limestone, and also to that to which the name drusy is sometimes applied.
Related to Italian miarole. (Wiktionary)
We have begun a study of porphyritic pyroxene rhyolite, erupted as pyroclastic flow, and its intrusive equivalent, ejected during the same eruption as blocks of miarolitic granite with spectacular granophyric groundmass.