umptekite

Noun

 * 1)  A syenitic rock consisting of microperthite, arfvedsonite, aegirine and, possibly, nepheline.
 * The rock-mass in which this umptekite form of hornblende occurs may therefore be called umptekite gabbro.
 * The rock-mass in which this umptekite form of hornblende occurs may therefore be called umptekite gabbro.