## 5 Discussion  
The productivity of dimension stone quarry mainly depends on the extractable block size and shape [2]. The shape and volume of the blocks are crucial factors and are controlled by the discontinuity pattern [2]. The External Dinarides orogen is mostly built from a \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Class** & **Very small** & **Small** & **Moderate** & **Large** & **Very Large** & **Crushed** \\ \hline J\({}_{\rm V}\) (m\({}^{-3}\)) & \(<\)1 & 1–3 & 3–10 & 10–30 & 30–60 & \(>\)60 \\ \hline \end{tabular}
\end{table} 
Table 4: Classification of degree of joint of rock mass according to the Volumetric Joint Count (Jv) [47]. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Drillho** & **Fracture Set** & \begin{tabular}{c} **Drillho** \\ **Depth/Interval** \\ **Length** \\ \end{tabular} & \begin{tabular}{c} **Apparent Fracture** \\ **Spacing** \\ **(m)** \\ \end{tabular} & \
\begin{tabular}{c} **The Average Angle** \\ **between Fracture and** \\ **Drill Hole Axis** \\ \end{tabular} & **Sin\(\delta\)** &
\begin{tabular}{c} **True Fracture** \\ **Spacing** \\ **(m)** \\ \end{tabular} & **1/d** \\ \hline \hline B-3 & S\({}_{0}\) & 79.40 & 4.20 & 45.00 & 0.71 & 2.97 & 0.34 \\ \hline B-6 & S\({}_{0}\) & 53.50 & 2.90 & 40.00 & 0.64 & 1.86 & 0.54 \\ \hline B-7 & S\({}_{0}\) & 83.00 & 7.70 & 40.00 & 0.64 & 4.95 & 0.20 \\ \hline B-9 & S\({}_{0}\) & 73.80 & 7.37 & 45.00 & 0.64 & 5.21 & 0.45 \\ \hline B-1 & S\({}_{1}\) & 44.00 & 8.42 & 31.41 & 0.52 & 4.39 & 0.23 \\ \hline B-3 & S\({}_{1}\) & 79.40 & 11.92 & 17.70 & 0.30 & 3.63 & 0.28 \\ \hline B-5 & S\({}_{1}\) & 44.50 & 2.93 & 12.80 & 0.22 & 0.65 & 1.54 \\ \hline B-6 & S\({}_{1}\) & 53.50 & 1.73 & 16.61 & 0.29 & 0.50 & 2.02 \\ \hline B-7 & S\({}_{1}\) & 83.00 & 3.93 & 17.67 & 0.30 & 1.19 & 0.84 \\ \hline B-9 & S\({}_{1}\) & 73.80 & 5.08 & 23.63 & 0.40 & 2.04 & 0.49 \\ \hline B-1 & S\({}_{2}\) & 44.00 & 3.15 & 29.88 & 0.50 & 1.57 & 0.64 \\ \hline B-3 & S\({}_{2}\) & 79.40 & 4.82 & 11.81 & 0.20 & 0.99 & 1.01 \\ \hline B-5 & S\({}_{2}\) & 44.50 & 2.76 & 25.83 & 0.64 & 1.77 & 0.56 \\ \hline B-6 & S\({}_{2}\) & 53.50 & 3.89 & 26.91 & 0.45 & 1.76 & 0.57 \\ \hline B-7 & S\({}_{2}\) & 83.00 & 2.72 & 10.40 & 0.18 & 0.49 & 2.03 \\ \hline B-9 & S\({}_{2}\) & 73.80 & 2.13 & 23.71 & 0.40 & 0.86 & 1.17 \\ \hline B-3 & S\({}_{3}\) & 44.00 & 6.70 & 10.25 & 0.18 & 1.19 & 0.84 \\ \hline B-6 & S\({}_{3}\) & 53.50 & 5.01 & 21.67 & 0.37 & 1.85 & 0.54 \\ \hline B-7 & S\({}_{3}\) & 83.00 & 3.72 & 14.47 & 0.25 & 0.93 & 1.08 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Spatial distribution properties: apparent fracture spacing (S\({}_{\rm m}\)), average angle between fracture and drill hole axis and true fracture spacing (d) for each interpreted discontinuity set, and Volumetric Joint Count (J\({}_{\rm V}\)) for the discontinuity pattern system. thick succession of often tectonically disturbed carbonates, which resulted in relatively small deposits (on the global scale) of high-quality dimension stone. These conditions demand challenging geological investigations in the \"pre-quarry\" phase to find the optimal quarry location. All necessary surface geological investigations were made (geological mapping, stratigraphy, structural research, petrography, mechanical properties), but since the terrain is rocky, impassable, and covered by vegetation, a small number of fractures was measured. Drillhole geophysics and the Optical and Acoustic Televiewer surveys were too expensive, so we were challenged to find a new method to measure fractures in the drill holes. A borehole camera with the bottom and side camera's spatial orientation was used to measure fracture orientation parameters (Figures 4 and 5). Fractures were measured, then analyzed in stereonets by cluster analysis to define fracture sets. Four preliminary sets were defined, of which one is bedding (S0), one is tensional fracture set (S1) perpendicular to the stress orientation and subparallel to the fold axis, and two sets were defined as conjugated shear fracture sets (S2 and S3).