Germanium is mostly developed from sphalerite zinc ores but can also be known for being extracted from fly ash coal (created from coal electric power crops) and several copper ores.Nghiên c?u c?a FDA ??a ra k?t lu?n r?ng germani, khi s? ??ng nh? là ch?t b? sung dinh d??ng, "th? Hello?n m?t s? nguy hi?m ti?m tàng cho s?c kh?e con ng??i".[six