Textural, mineralogical and compositional characteristics of basaltic glass
es from the Central Indian Ocean show them to be altered to varying extents
through their interaction with the seawater, resulting in the formation of
palagonite. The major chemical changes are the loss of Si, Mg and Ca and a
gain of Na and K whilst, Fe and Ti remained immobile. It reflects that the
basaltic glasses have undergone initial to intermediate stages of palagoni
tisation under low temperature oxidative alterations. Subsequent accretion
of ferromanganese oxides over the glasses have halted the progress of alter
ation.