the material is definitely cotton. i don't think the lace is nylon. as for the button....?? it is very smooth with a pearly opalescence to it. it is mostly machine sewn, but there is some hand stitching on it here and there. the piece was completely ivory with age when i found it, but thankfully it all soaked out. i was wondering (hoping!) that maybe it had been for a younger girl as it isn't full length. it is truly a beautiful piece.