DEGREE OF CRYSTALLINITY Flashcards
1
Q
holohyaline
A
rock composed entirely of glass; no crystals visible even with magnification
indicates cooling so rapid no crystal growth could occur
2
Q
holocrystalline
A
rock composed entirely of crystals(which may or may not be visible without
magnification)
indicates cooling sufficiently slow to allow complete crystallisation to occur
3
Q
hypocrystalline
A
rock composed both crystals/glass
indicate period or relatively slow cooling follwed by quenching f remaining magma