The Turkish lira firmed as far as 1.8510 against the dollar on Friday after the central bank sold dollars on the forex market, but subsequently surrendered much of its gains while stocks weakened a touch. The lira traded at 1.8860 per dollar, still sharply firmer than 1.9185 on Thursday afternoon, while it firmed as far as 2.1296 against its euro-dollar basket right after the central bank intervention, from 2.1977 earlier and a previous close of 2.1992.