OCT means octagon cut, an eight-sided shape that works beautifully with corundum. The broad facets and wide table of the octagon cut produce substantial brilliance. OCT corundum gems have tremendous flash and fire, with precise cutting that balances the eight facets. Each stone is carefully aligned to optimal the light return. Vibrant hues like ruby and pink sapphire really pop in an OCT shape. The straight lines and sharp corners create a clean, contemporary look. Despite the defined corners, OCT shapes retain durability thanks to corundum’s hardness.