Using a lightweight tile backer board for your mosaic will provide you with a waterproof option for indoors and outdoors. Please make sure to seal the edges if it is being used outdoors. The boards come in different sizes and thickness, if your mosaic is larger , it will be better to use a 2cm board, so it can hold the weight of the glass.The boards can be easily framed, as you would frame a normal picture.
Hint: Frame the board first, so you know exactly how far to the edges you can glue the Smalti.
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