This bottle was manufactured in India. There are air bubbles in the glass and the marble inside is cobalt blue.
The Codd bottle was designed and manufactured with thick glass to withstand internal pressure, and a chamber to enclose a marble and a rubber washer in the neck. The bottles are filled upside down, and the pressure of the gas in the bottle forced the marble against the washer, sealing in the carbonation. I have not attempted to clean the bottle other than with a little water.