Aegirine - Pyroxene Group.
 
 
From: Malosa Mts., Zomba, Malawi.
 
 
Sub-euhedral, monoclinic, tabular, dark green almost black, opaque prismatic crystal, measuring 6.0 x 4.5 x 1.5 cm. Formed in an alkaline pegmatitic context. 
 
 
Supplied in a 6x6 cm cardboard box with identification.