What is the difference between KDM mark and 916 hallmark stamped on any gold jewellary?

Here are 2 lists which should explain gold and silver standards It is the Hardness of Gold this list may help CTOP 24 999 99.9 Three nines 24 990 99.0 Two nines, Minimum allowed 22 916 91.6 Indian subcontinent 21 875 87.5 Arabic countries (19.2) 800 80.0 Standard in Portugal 18 750 75.0 Standard caratage 14.8 620 62.0 Dental Gold Minimum 14 585 58.5 583/58.3% in USA 10 417 41.7 Minimum in USA 9 375 37.5 U.K. standard 8 333 33.3 Minimum Germany Quality of the silver 916 parts silver and 84 parts impurities t.1000 (Japan, ?) .999 Fine Silver .980 (Mexico, ?) .959 (Czechoslovakia, ?) .950 Britannia (U.K.) - (France, Japan, Netherlands, Switzerland, Italy, Yugoslavia, Bulgaria, Romania, Hungary, ?) .940 (Poland, Mexico, ?) .935 (Austria, Germany, Switzerland,?) .934 (Netherlands, ?) .930 (Netherlands {pseudomark 19cent.}) .925 Sterling (U.K., U.S., becoming worldwide) .916 (Finland, Portugal, Russia, Romania, Spain, ?) .915 (Spain, ?) .900 Coin (u.s) - (China, Argentina, Switzerland, Italy, Yugoslavia, Czechoslovakia, Hungary, Japan, Egypt, ?) .875 (Russia, Baltic States, Finland, Switzerland, Romania, ?) .840 (Russia, ?) .835 (Germany, Netherlands, Belgium, Austria, ?) .833 (Portugal, Netherlands, ?) .830 (Norway, Denmark, Sweden, Finland, ?) .826 (Denmark) .813 (Finland) .800 (Germany, Italy, France, Netherlands, Switzerland, Spain, Argentina, Japan, Romania, Egypt, ?) .750 (Germany, Italy, Spain, Yugoslavia, Czechoslovakia, Romania, Bulgaria, Hungary, Romania, ?) .700 (Lebanon, ?) .600 (Egypt, ?)