Authentic Murano Glass Blown in the furnaces of Murano. These are part of our Finestra with a transparent Amethyst (purple) with black filigrana which makes the windows with its transparent sides. This is in the shape of a cipolla (onion) a squashed round which measures approximately 15mm across the way the hole runs and about 20mm in diameter. The hole size is a nominal 3mm in diameter but will vary because the maestro is blowing melting glass.