PT Semen Gresik, an Indonesian cement maker, Monday said cement sales in January rose 3.8 per cent on-year to 1.233Mt due to an increase in domestic sales.  Semen Gresik’s domestic cement sales during the month rose 9.6 per cent vto 1.062Mt from 969,309t in January last year.  Its cement exports, however, slumped 22 per cent on-year to 170,779t.  Semen Gresik didn’t comment on its sales performance.  According to data from Indonesia’s cement producer association, national cement sales in January rose 3.6 per cent to 2.972Mt from 2.87Mt a year earlier.