ABSTRACT: Using some simple calculation techniques the ma jor chemical analyses results of magmatic rocks can be transformed in into the parameters which present useful informations about petrological determinations, The parameters which were also na med as Niggli values achieve the differ antiation trends of magmatic rocks, their magmatic provinces and alkali characters of chemically analysed rocks. They also give important informations about the then type of magmas which rocks are derived NIGGLI which was written in QUICKBASIC calculates the Niggli parameters of major chemical analyses, evatutes the results in terms of petrochemistry and presents their variations as graphics. The compiled form of program is aproximately 356 kbyt, This program operates under the IBM compatible personal computers have a VGA graphics card