Sea Plate | Caspian This plate, crafted from polished onyx, features graceful, wavy contours that evoke the Caspian Sea shape. The polished surface accentuates the stone's unique veining and warm translucence, making it a stunning fusion of elegance and organic beauty. Butterfly Shape. Please note: Due to the natural characteristics of onyx, no two pieces are exactly alike. If you'd like assistance selecting a specific colour variation or would like to see the available pieces before purchasing, please contact us, we're happy to help you find the perfect one.