Mosaic done in glass goes back to as early as 2500 BC, but it wasn’t until the 3rd Century BC that innovative artisans in Greece, Persia and India created glass tiles. On the other hand, clay tiles are dated way back to 8000 BC.
The hurdle for the development of glass tiles seemed to be the requirement of high temperatures to melt glass, and the complexities of mastering various annealing procedures for making it tougher and less brittle.
Now, with technological breakthroughs, glass tiles are being acknowledged for functional wall uses and as accent tiles. Their innate properties to impart dominant colours and still reflect light have them as a designer’s delight, much as their imperviousness to water makes them get the marks for their functionality. But laying these glass micro-tiles or handling them in bigger sizes is tricky, as their rigidity compared to ceramic or porcelain makes them break due to the force and stress applied while laying them, say experts.
Irregular shapesSmalti, hand-cut opaque glass tiles, were used in the rich decorative mosaics of the Byzantine Empire and Renaissance Italy. Much unlike the uniform shapes that modern glass mosaic tiles comes in, Smalti tiles are not known to be moulded into uniform shapes, say industry experts.
Smalti is made by mixing glass and various minerals according to traditional recipes and the furnace-melted mixture is then poured onto a slab for cooling and later cut by hand into rectangular pieces that are about 1/2" or smaller. They don’t come in perfect rectangles, but vary in thickness, shape, size and colour. These natural variations more than helped Smalti be perfect mosaic materials enabling artists to create their own innovative images.
During the Byzantine era, Constantinople became the centre of the mosaic craft, and the use of glass mosaic reached the greatest artistic expressions.
Traditional Smalti tiles are still found in European churches and ornamental objects. In the 1920s, mass production methods enabled these tiles find their way into many middle-class homes. New methods of manufacturing them in the 1990s included taking used glass and recreating it as ‘green’ tiles, resulting in a resurgence of interest in glass tiles for floor and wall cladding. It is now commonly used in kitchens, spas, and bathrooms. And while Smalti tiles are still popular and named in more ways then one, small and large format glass products using cast and fused glass methods are common.
The late 1990s also saw these glass tiles being coated on the back with a receptive white coating. This has allowed impregnation of heat-transfer dyes by a printing process reproducing high resolution pictures and designs. Custom-made printed glass tiles for glass tile murals are now seen in most showrooms as murals to exhibit products. These are especially practical in kitchens and showers, where cleanser and moisture resistance are important.
A challenge“This kind of tiling for creating a mural on the wall is a challenge” says S. Muralidharan of Studio Infiniti, dealing with variety tiles. “In any wall mural of a huge kind there would be a minimum of three families of tiny tiles with varied thickness blended for the design to take the right shape. There will be places where even a 10mm x 10 mm tile has to be cut to get the design right.”
Italian and Indian versions in strips are stuck together to the wall with polymer modified adhesives for lifetime grip and special grout for matching the tile colours. The grouts used for permanent bond are anti-algae, anti-fungal and waterproof.
The basic range of glass mosaics starts at Rs.250 per sq. ft and goes on to thousands depending on the materials used.
