Ruby in Marble

Description

The marble quarries of Sivec, near Prilep in North Macedonia, have been known since antiquity for their brilliant white ornamental stone — and for the ruby crystals embedded within it. These rubies (red gem corundum, Al₂O₃) occur as flattened hexagonal tablets and irregular masses of deep red to pink-red, set against a pure white crystalline marble matrix.

The strong colour contrast between vivid ruby and snow-white marble makes Sivec specimens among the most visually striking mineral combinations in European mineralogy. Corundum reaches hardness 9 on the Mohs scale, making ruby the second hardest natural mineral after diamond.