If you have experience in the Sri Lankan gem market, you will notice that crystal-form gemstones are quite commonly found. However, certain varieties are rarely seen in their natural crystal form, particularly within Sri Lanka.

From personal experience in the trade, we regularly come across crystals of yellowish sapphire — essentially yellow corundum. By contrast, encountering ruby in its natural crystal form is a genuinely rare occurrence.

Ruby, the red gem variety of the mineral corundum (aluminium oxide, Al₂O₃), owes its vivid colour to trace amounts of chromium. In its crystal form, ruby typically grows in a trigonal crystal system, most often developing as flat, tabular hexagonal crystals or stubby barrel-shaped prisms. The natural growth patterns frequently display distinctive striations — fine parallel lines running across the crystal faces — which are a hallmark of corundum’s formation process. In Sri Lanka, ruby crystals are predominantly found as waterworn pebbles in alluvial gem gravels rather than in their original host rock, which is why intact, well-formed crystals are so seldom encountered.

Take a look at this ruby crystal, showcasing its distinctive growth pattern — a rare and remarkable find from the island’s gem-rich terrain.