Choosing the right materials

When deciding what materials to use in your mosaic,incorporated into a mosaic if you wish --­ metal,
there are a number of practical things to take intoplastic, stone, even teeth! --­ if they are stuck
account: Are the materials suitable for where thedown firmly.
mosaic will be placed or used? For example, if theBacking materials If you browse through books or
mosaic will go out of doors, will the materials surviveweb sites you'll see that virtually any object can be
frost and rain? If the mosaic will go under foot, willmosaicked. The most commonly used backing is
the materials stand up to wear and tear? Will thewood. This should be of a kind that will not warp, for
materials will give you a flat surface, if this is needed?example a fibre board (such as MDF) or plywood. If it
How much of the materials will you need and howwill go out of doors, an exterior grade wood should
much will they cost? Notes on various materials:be chosen. The back of a tile can be used very
Crockery: Often cheap (or free) to get.successfully as a mosaic base, as it is porous and
Can be quirky, fun and evocative ("memoryware").gives very good adhesion.
Can be difficult to get flat surfaces, or a lot theIt is usual to prepare wooden surfaces by priming
same. May be damaged by frost. The material ofand scoring them. Priming involves painting on a coat
choice for pique assiette style.of diluted PVA glue (about one part glue to 5-10
Household tiles: Can be fairly cheap, particularly if youparts water). This seals the surface, meaning that
can get offcuts or spares. Second-hand tiles strippedglue and grout will not dry too quickly. Scoring lines
off walls usually have adhesive on the back, which iswith a craft knife or Stanley knife makes the surface
a problem to clean off. Vary a lot in quality, thicknessrougher, giving a better grip.
and ease of cutting between different types. May beAdhesives Choice of adhesive is important. For most
damaged by frost.purposes, PVA (Poly Vinyl Acetate) glue is ideal (also
Vitreous glass: (right) More expensive.known as "white craft glue"). This is widely available.
Wide range of colours available. Flat surface. SuitableGenerally the most cost-effective way of buying it is
for outdoor projects.in quantity from a builders' merchant. It is fairly quick
Can be tricky to learn to cut and shape.drying (within several hours), moderately
Smalti: Expensive. Wide range of colours available.water-resistant when dry, and relatively low hazard.
Classical appearance.Household tile adhesive: Good "grab" for 3-D projects.
Glass: Stained glass comes in a range of colours. CostUseful where the tesserae are not flat, as it can fill
depends on source - scrap glass relatively cheap,the space behind. Generally relatively low hazard.
may vary in thickness. Can be used outdoors. BackingEpoxy resin: Very strong. Fast setting versions
and adhesives must be chosen with care, as may beavailable. Good for non-porous contacts e.g. with
visible through glass. Mirror glass can be verymetal, or where quick repairs needed. High hazard,
effective.not pleasant to use.
Shells: Cheap. Fun to collect.Bathroom sealant: Very effective for
Frost-hardy. Too porous to be grouted in the normalceramic-to-ceramic bonds. High "grab", so good for
way, as they will stain.3-D work. Can work out relatively costly.
Found objects: Many found objects can be