Melting glass objects, such as beer bottles, is often done in order to make decorative art with the melted glass. In order to melt a glass bottle you need access to a kiln. Using the kiln, you can melt chunks of the bottle glass down to a desired shape or pour the melted glass into a mould. The melted glass can be reformed into a shape for jewellery or any other type of decorative household object.
With running water, clean out the bottle you wish to use. Let the bottle dry.
Place the bottle into two overlapping plastic bags. Close the bags and then carefully smash the glass with a hammer. Smash the glass until you have only small pieces.
Open the bag and remove the bigger pieces of glass that you can safely pick up with your fingers. Place those pieces onto your kiln shelf in a metal mould that is safe for use in a kiln. Carefully arrange the pieces on your shelf with your fingers.
Use a spoon to remove any of the tiny pieces of the broken glass and gently pour the small pieces into the mould on the kiln shelf. Close your kiln door after the mould pieces are arranged.
Set your kiln temperature to 260 degrees Celsius (see References). Once the temperature reaches 1000 degrees, fire the glass in the kiln for at least 10 minutes.
Bring the kiln temperature up to 1425 degrees until your melted glass has the shape you want within the mould. Turn off your kiln and allow for the temperature to cool down to under 100 degrees before removing the glass.