Correct spelling for the English word "fahlers" is [fˈɑːləz], [fˈɑːləz], [f_ˈɑː_l_ə_z] (IPA phonetic alphabet).
Grey copper-ore; the type of a family of minerals containing copper.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.