A mosaic is a picture or design constructed from smaller separate pieces, in this case, glass. Each piece of glass is affixed onto a surface (wood, concrete, etc.) and then grouting is applied to seal the layer. Different varieties of glass can be incorporated together to create the design. For example, the Glass Visions piece above employs fused glass and unfired sheet glass. The "Fountain" has fused glass, unfired sheet glass, and found objects. This can also happen with fused pieces incorporated with stained glass pieces and so on.