In geological constructing of Vlahna deposit participate ultrabasic rocks mainly represented by serpentinized hartzburgite, intensively serpentinized hartzburgite, serpentinized hartzburgite - dunite, serpentinized dunite - hartzburgite and serpentinized dunite sequences. Harcbrugite occupy most of the area of the ore deposit (Zhukri E , Sokoli M , 1987) which are intercalated with lenses and large bandings of dunite which gradualy pass in the hartzburgite – dunite sequence. The contents of the pyroxene (rhombic type) ranges from 5-10% to 30%. In most cases, the hartzburgite rocks are constituted by serpentine of the krizotil – antigorite type that originated from olivine and bastite pyroxene. The structure of the rock is porphyroclastic. The olivine is preserved as relicts with loop - island structure within the mass of the network structure of krizotil type. The accessory mineral is encountered chromspinel that constitute 1-2 % of the rock mass. Within dunite often are meet chrmite schliers. Dunite spread mainly in the form of the stratification belts 5-50 m thick, which are followed in strike up to several kilometers. Within these stratifications besides the chromite ore bodies are found lenses of intensively serpentinized hartzburgite having the same orientation with ore bodies and the dunite lenses, which is approximately north – south striking and strong dipping towards west (See geological
map at scale 1: 10,000, (Figure 4). Within dunite lenses are discovered chromite ore bodies which constitute the big Vlahna ore deposit (See geological map at scale 1:4000, (Figure 5a and 5b). The ore bodies are of the banding and disseminated types grading 10 - 40 % Cr2O3, averaging 28 % Cr2O3.
The data show that the ore field of Vlahna represents a major source of chromium ore. This ore field is composed of a big lens – layered ore body, accompanied by a number of parallel small lens – layered ore bodies (Zhukri, E. et. al., 1987; Sokoli, M., 1986; Selimi, R., et.al., 1996). This body outcrops in the north of profile 13 and between profiles 15-22 and 30-34, (Figures. 4, 5a, 5b, 6, 6.1, 6.2, 6. 3). On the basis of previous superficial prospecting - exploration works was created idea that these ore bodies are separate bodies, while further prospecting - exploration works, especially drillings, have confirmed continuity in depth as a single ore body, separated in blocks by faults of the multiple steps.