Plutonic rock composed chiefly of dark-coloured minerals such as olivine and pyroxene that contain abundant magnesium and iron. It is derived from magnesium and ferric (iron). The term mafic also applies to dark-coloured minerals rich in iron and magnesium as a group. Mafic rocks usually refers to dark-coloured igneous rocks such as basalt, but can also refer to their metamorphic counterparts.
Modelled on the French tricolour, the vertical stripes represent liberty and revolution. The almost square proportions of the flag are unusual. Effective date: 23 January 1831.