porphyritic
adjective
por·phy·rit·ic ˌpȯr-fə-ˈri-tik 
1
: of or relating to porphyry
2
: having distinct crystals (as of feldspar) in a relatively fine-grained base
Word History
Etymology
Middle English porphiritike, from Medieval Latin porphyriticus, from Greek porphyritikos, from porphyritēs (lithos) porphyry
First Known Use
15th century, in the meaning defined at sense 1