A good adhesive to attach glass pieces is Loctite glass glue. Another very strong adhesive for glass is ultraviolet (UV) glass glue, which provides a permanent bond. However, this glue requires the use of a UV lamp for curing.
Loctite glass glue is dishwasher safe and heat resistant. It dries clear and can be used on different glass types, including stained, crystal, colored and opaque. This product can also be utilized to bond glass to metal or nonporous materials.
UV glass glue is another type of product that provides a strong glass to glass bond. However, the product should not be used on glass that is in area which has too much water exposure. To use this product, the glued glass pieces are placed under an UV lamp for about 5 minutes. This type of adhesive is useful for glass-etching projects.