We’re spoiled for choice with the variety of materials suitable for creating mosaic work. Each material has its unique qualities, which need to be considered when you’re deciding what to use in your work. From glass to ceramics and stone, materials span a range of textures, finishes and colours. So how do you decide what to use? The answer may depend on many factors, including cost, ease of use and suitability for exterior use, to name but a few. In this advertorial, brought to you in partnership with Mosaic Trader and The Craft Kit (which was first published in Issue 8), we give you the lowdown on some of the most popular materials, to help you choose the type of materials you’d like to use in your mosaic work.
By Rhona Duffy in partnership with Mosaic Trader and The Craft Kit
Vitreous glass mosaic
Used to line swimming pools, vitreous glass mosaic tiles are one of the most commonly available types of materials. Made of glass, their surface is shiny and reflective – they can be matt, iridised, transparent or opaque. There is a wide range of colours to choose from. The lightest colours tend to be the cheapest, while the brightest colours with metal veins are the most expensive.
The smooth side is usually face up, with the textured side face down. They’re typically bought by the sheet, on mesh or paper (12″ x 12″ / 30cm x 30cm). It’s also possible to buy loose tiles, which are usually more expensive. As they’re manufactured, they’re regular in size (usually about ¼″ x ¼″ / 2cm x 2cm). You can cut them with regular or wheeled nippers.
Ease of cutting: ✓✓✓✓✓
Exterior use: ✓✓✓✓✓
Cost: ✓✓✓✓
Groutability: ✓✓✓✓✓
Tip: To soak off the brown backing paper from sheets of vitreous mosaic tiles, place them in a bowl of warm water. They’ll separate after a few minutes. Rinse your tiles with more warm water and lay them out over a towel to dry.
Metallic glass tiles
Foil or glitter-backed crystal glass tiles are growing in popularity. They’re made from float glass that’s glued to coloured foils or glitter powders, coated with epoxy and heat-bonded in a kiln. Each tile is ¼″ x ¼″ or 2cm x 2cm. The colour is sensitive to light and will fade with exposure to direct UV radiation, making these tiles less suitable for exterior use. Cut them with regular or wheeled nippers.
Ease of cutting: ✓✓✓✓✓
Exterior use: ✓
Cost: ✓✓✓
Groutability: ✓✓✓✓✓
Tip: To check if a tile is backed with a material, hold it horizontally – you’ll notice a layer of clear glass covering the top of a tile.
Smalti
Smalti is the Roman word for “melt”. The art of producing smalti is believed to have been born in Egypt, continued in Persia, and then in Greece where the Romans learned it. Glass is melted in a cauldron and poured out into a metal sheet where it’s pressed down. In Italy, it’s called a pizza, in Mexico a tortilla. The Italian pizza is poured to a thickness of approx. ⅜″ (10mm) or the tortilla ¼″ (6mm). Italian smalti (pictured) is cut into thinner pieces (like small bricks) to expose the inside of the pizza. This inside (riven) side will be the working surface of the material. Due to the varying thickness of Italian smalti, you need to use the reverse method if you want a smooth surface on your finished work.
Mexican smalti is cut larger into irregular squares (approx. ⅝″ or 15mm) on the visible working side with a fairly consistent ³⁄₁₆″ (5mm) thickness. The working surface of the Mexican smalti is the top or bottom of the tortilla and it has a smooth surface without bubbles. It can be set direct with or without grout. You can turn the Mexican smalti on edge to add texture to your piece. Usually cut with a hammer and hardie, it’s also possible to cut smalti with wheeled nippers (though some pieces may not fit in the jaws depending on the type of nippers).
Emaux De Albertini smalti is made according to the traditional recipe of the Albertini foundry in France.
Dynasty smalti from China is a more economical option and can be useful in backgrounds or for bridging tones and shades. The colours tend to be less vivid than Italian smalti if they’re made from recycled glass.
Ease of cutting: ✓✓✓
Exterior use: ✓✓✓✓✓
Cost: ✓✓
Groutability: ✓✓✓
Tip: Italian smalti can be grouted but its uneven surface has little holes made by air bubbles escaping during the cooling process – these can trap grout, which is difficult to remove and can make the finished piece look spotty. Most traditional smalti work is not grouted for these reasons and, instead, it “self-grouts” – as you push smalti into adhesive (thinset), it pushes up in the gaps between the smalti. We recommend testing before grouting your work.
Gold and silver smalti/metal-leaf glass tiles
Containing real gold or silver in the glass tiles, unsurprisingly, these are the most expensive mosaic materials. But they can make a big impact on a piece even when they’re used sparingly.
You can choose flat or wavy effects and they’re sold individually or on sheets. You can cut them with regular or wheeled nippers, or a hammer and hardie.
Ease of cutting: ✓✓✓✓✓
Exterior use: ✓✓✓✓✓
Cost: ✓
Groutability: ✓✓✓✓✓
Art glass
Stained glass is increasingly being used in mosaic work. With the flexibility to cut it into intricate shapes if you learn how to do this, you can make a statement in your work using glass pieces. Or you can cut it up into smaller pieces and use it as more conventional mosaic tesserae. You can also buy pre-cut shapes, including leaves, circles, diamonds and more. It’s available in transparent, semi-transparent or opaque, with a wide range of colours. You can cut glass with regular or wheeled nippers, or by using a glass scorer and running/grozing pliers.
Ease of cutting: ✓✓✓
Exterior use: ✓✓✓✓✓
Cost: ✓✓✓
Groutability: ✓✓✓✓✓
Tip: If you’re using transparent or semi-transparent glass in mosaic work, you’ll need to use a suitable glue / adhesive (thinset) that doesn’t show beneath the glass and that allows the light to shine through. White adhesive (thinset) works well for this purpose.
Glass shapes
From geometric shapes like rectangles, rounds and triangles, to petals, leaves and peacock eyes, Mosaic Trader and the Craft Kit stock the widest range of glass shapes and nuggets available anywhere in the world.
Ease of cutting: ✓✓✓✓
Exterior use: ✓✓✓✓✓
Cost: ✓✓✓
Groutability: ✓✓✓✓✓
Mirror
Mirror adds a wonderful quality to mosaic work – some works are even made completely from mirror. You need to ensure you’re using the right glue/ adhesive though. If you apply tile adhesive (thinset) to pieces of broken mirror, it will oxidise the silver backing and destroy the reflective property of the mirror. Mosaic Trader and the Craft Kit stock a new laser-cut mirror in hard-to-find ⅛″/4mm thickness. It’s made from high-quality silver mirror and is resistant to tarnishing as well as easier to mosaic due to the improved thickness. It’s available in a range of shapes and sizes, loose or mounted on mesh, and is UVA and frost resistant. But be aware that constant moisture may tarnish the mirror backing.
Ease of cutting: ✓✓✓✓
Exterior use: ✓✓✓✓
Cost: ✓✓
Groutability: ✓✓✓✓✓
Ceramic tiles
Ceramic tiles are usually about ¾″-1″/20mm-25mm square and are available glazed or unglazed. Glazed ceramic tiles are not as durable or weather resistant as porcelain or glass tiles. If your project is subject to freezing weather, you should consider Winckelmans, Mazurka or glass tiles. Porcelain tile is weather resistant. Winckelmans (pictured) is a French porcelain manufacturer of quality unglazed quarry tiles since 1894, the tile of choice for traditional Roman style mosaic.
Cinca is a Portuguese line of unglazed porcelain in a 1″ x 1″ / 25mm x 25mm size. It’s also possible to buy a range of ceramic shapes to be used in mosaic projects – when buying, check the notes to see if they’re suitable for exterior use or not.
Ease of cutting: ✓✓✓✓
Exterior use: ✓✓✓
Cost: ✓✓✓
Groutability: ✓✓✓✓✓
Tip: To test a ceramic tile’s suitability for exterior use, put a spoon of water on the top of the surface – if it’s still there after a few hours, it’s not porous. If it’s absorbed, it means it’s porous so exterior use is not advised.
Marble
Marble was traditionally used in Greco-Roman mosaics. It’s an expensive material and there isn’t a wide range of colours available. While the colours are usually soft and muted, a more intense effect can be achieved by polishing, sealing, waxing or varnishing. Marble weathers naturally when exposed to the elements. Marble is a good option for flooring. You can buy pre-cut tesserae or rods that you cut up yourself. The classic method of cutting marble is using a hammer and hardie. A wheeled nipper may be used – it’s worth noting that the tiles will wear out more quickly, however, and they can crumble when being cut this way.
Ease of cutting: ✓✓✓
Exterior use: ✓✓✓
Cost: ✓✓
Groutability: ✓✓✓✓
Tip: Always seal marble with beeswax or stone sealant before grouting as coloured grout may stain the tesserae. Create a more polished finish by using a stone sealant in either matte or gloss.
Connect:
www.thecraftkit.com
www.mosaictraderusa.com
www.mosaictrader.com