Method for the production of formula (I) lumateperone or its acid addition salts so that the enantiomer compound with stereochemistry 6bR,10aS




is separated form the cis racemate using resolution and the formula (II) stereoisomer is alkylated with 4-halo-4′-fluoro butyrophenone (X=I, Br, Cl) to produce the formula (I) lumateperone, or optionally its acid addition salt. The object of the invention also relates to the amorphous form of the morphologically uniform p-toluenesulfonic acid salt of lumateperone and to the naphthalene-2-sulfonic acid salt of lumateperone, to the 1:2 stoichiometry salt of lumateperone formed with naphthalene-2-sulfonic acid.