Apparatus for precisely cutting and polishing gemstones, said apparatus comprising a precision divider , a supporting device arranged to be located at a work bench comprising a lap for attachment of grinding and polishing devices, wherein the precision divider is attached pivotal to the supporting device , arranged to be pivoted and fixed with its longitudinal axis at a desired angle with the supporting device , said precision divider further comprising a mandrel exhibiting a dopstick recess arranged to accommodate a dopstick (122; 500) carrying a gemstone , and means for rotating the precision mandrel about the longitudinal axis and locking the mandrel against rotation during grinding and polishing of the gemstone , wherein the precision divider comprises a housing accommodating the elongate mandrel having a first end in which the dopstick recess is formed, and a second end exhibiting a precision graduated disk and a precision dividing gear , said mandrel , precision dividing gear and graduated disc being lockable at a desired rotational position with regard to the longitudinal axis by a mandrel rotation locking device , and wherein the supporting device comprises a frame device arranged to be attached to a work bench via a support column in an adjustable manner both in the horizontal plane and in the vertical direction, thus enabling positioning of the frame device and the precision divider at a desired elevation and desired horizontal orientation, said supporting device further including a vertical angle adjustment device comprising a precision divider vertical angle dial and an angle locking device , arranged to lock the precision divider in the desired angle position, characterized in that said mandrel , precision dividing gear and graduated disc are arranged rotary in relation to the housing , and in that the supporting device further comprises a fine vertical angle adjustment means arranged to perform fine angle adjustment of the precision divider as a supplement to the vertical angle adjustment device. the precision divider comprises a housing accommodating the elongate mandrel having a first end in which the dopstick recess is formed, and a second end exhibiting a precision graduated disk and a precision dividing gear , said mandrel , precision dividing gear and graduated disc being lockable at a desired rotational position with regard to the longitudinal axis by a mandrel rotation locking device , and wherein the supporting device comprises a frame device arranged to be attached to a work bench via a support column in an adjustable manner both in the horizontal plane and in the vertical direction, thus enabling positioning of the frame device and the precision divider at a desired elevation and desired horizontal orientation, said supporting device further including a vertical angle adjustment device comprising a precision divider vertical angle dial and an angle locking device , arranged to lock the precision divider in the desired angle position, characterized in that said mandrel , precision dividing gear and graduated disc are arranged rotary in relation to the housing , and in that the supporting device further comprises a fine vertical angle adjustment means arranged to perform fine angle adjustment of the precision divider as a supplement to the vertical angle adjustment device. <EOS>