How to Do Mosaic Stained Glass – Direct Method
There are two basic methods to mosaic work - the direct method and the indirect method. In the
direct method, the pieces of material you are going to mosaic with, known as tesserae, are directly
fixed top side up onto a base or substrate and then grouted. In the indirect method pieces are
temporarily fixed top side down onto a removable base material. This is (then) cast in its final
form and the temporary base material is removed to reveal the mosaic, top side up. The indirect
method is most often used when the finished surface needs to be extremely smooth.
Tesserae are the individual pieces of material you will arrange to form your mosaic. Most people
think of those little square pieces of tile seen in early Roman mosaics or in swimming pools. Today
the term applies to anything pieced together to form a design. Common tesserae include:
Traditional Tile Tesserae
- Vitreous Glass: Know as Venetian glass it is non porous, stain resistant, and frost proof. Common
sizes are ¾" (2cm) or 3/16" (1cm) squares with a flat top face and a ridged and beveled
back. They are available in a wide range of colors.
- Gold and Silver Leafed: Commonly found as ¾" (2cm) squares. They are made by sandwiching gold,
silver, copper or gold-alloy leaf between a clear top layer (sometimes colored) and a colored
(generally a transparent yellow, green or blue) base. They have flat or rippled surfaces.
Smalti: Handmade irregular rectangles of opaque glass. Generally about ¾" in size with a
pitted, irregular, and very reflective surface.
- Unglazed: Commonly found as 1" or 3/4" squares stuck to a paper or plastic mesh. The color
is uniform throughout the entire tile.
Glazed: Includes wall and floor tiles, crockery, pottery, tableware and others. The color is a fired
surface layer over a clay base. They are a rich source for color, pattern, and texture.
Includes everything from beach or river pebbles to marble, granite, slate and
modern day stone tiles. They have a wide range of colors, textures and surfaces. Also included are
semiprecious stones - turquoise, lapis lazuli, alabaster, quartz and agate.
China & Porcelain
A finer form of ceramics, they are a good source for interest, pattern and
Shells and Mother of Pearl
Mother of pearl is the lustrous inner surface of shells like oysters
and abalone. Commonly used shell forms include spirals, scallops, snails, etc. and cover a wide
range of color, luster and size.
Includes mirror, colored glass, sea glass, glass nuggets, marbles, and pressed glass jewels
Bone, metals, buttons... just about anything you want can become tesserae in
Selecting the Base
You can apply a mosaic to nearly any surface, so selecting the base material
becomes a matter of the shape you want, how it will be used, and where it will be used. When
selecting a base think about the following:
Is it strong enough to hold the combined weight of tesserae, adhesive, and grout?
Does the base shape have appeal and good proportions?
The shape should be suited to the size of tesserae you use. Gentle curves are easier, extreme curves
can require very small pieces in order to "bend" the tesserae with the curve and have a
Can you find the correct adhesive to adhere the mosaic pieces to the base?
Commonly used base materials include but are not limited to:
Wood: Can be cut to shape and size easily, making it ideal for many situations. You can mosaic on
most any wood surface, but be aware that no wood is 100% waterproof and wood can sag or warp. Using
a high grade plywood (at least ½" thick) will provide a rigid support and help counteract
warping. You will want to "tooth" (rough the surface of) and seal the wood before applying
the mosaic as added insurance.
Terracotta: Terracotta and clay objects offer a wide variety of shapes and sizes to mosaic on.
Cement: You can add mosaic to pre-made concrete objects like birdbaths, stepping stones and planters.
Glass: You can mosaic on flat sheets of window glass or glass items like bowls, votives, plates,
Net: This is a fine weave resin fiber that acts as a intermediary base. It is easily cut to any size
or shape. Generally the mosaic is fixed to the net, the excess trimmed and then embedded into
cement, or grouted and glued onto its permanent base.
- Walls, fixtures, plaster items, ceramics, containers, trays, found objects... use your
Selecting the Adhesive
The base material, tesserae, project use, and its location all influence
the type of adhesive you will choose. There is a 'glue' for every situation. Start by reading the
'applications' section on the package. Common choices include:
- Acrylic Based Adhesive: Sold under various brand names. For mosaics, thick white glues that dry
clear and labeled as PVA (poly vinyl acetate). Select brands that list as 'water resistant'. They
are often used for interior mosaics that won't be exposed to the elements. An advantage is that they
are very strong and can adhere tesserae to slippery surfaces like ceramic and glass. Diluted, it is
useful as a surface sealant prior to applying mosaic or as a strength additive to grout.
Cement Based Mortars: The traditional adhesive made by mixing powdered cement, sand and water. You
can also find quick setting, pre-colored, made for glass, Thinset, and traditional mixes. For
exterior use, use one that is waterproof and frost proof.
Epoxy Resins: A two part adhesive consisting of a resin and hardener mixed together right before
use. They will adhere tesserae permanently to metals. They are often messy, smelly and have
different windows of working opportunity before they set.
Other Choices: Silicone, silicone-based glues, ultraviolet curing glues, and construction adhesives.
Always check the package and match the adhesive to your tesserae, base material, and the object's
Beside a base, tesserae, and adhesive the only tool you'll really need to start with
is a tile nipper. All other tools can be commandeered household items. As you work with different
tesserae, bases, and adhesives you will find it useful to add specific tools to your arsenal.
Cutting Tools are used to shape and trim your tesserae
Tile Nippers are designed for cutting tiles. Good ones have tungsten-carbide cutting edges and
spring loaded handles. More expensive models have replaceable jaws and compound leverage. They are
suitable for most glass, ceramic, crockery, china, and the like.
- Tile Cutters are designed for scoring, cutting and snapping ceramic tile. They have a
tungsten-carbide wheel used to score, and a gripper used to break the tile along the score. They are
useful for long straight cuts and for use on wall and floor tiles.
- Glass Nippers have a set of disc shaped tungsten-carbide wheels set opposite on spring loaded
handles. They are used to cut glass, mirror, glass tiles, and the like in a manner similar to tile
Hammers of all types are useful. Ordinary household versions are suitable for breaking large tiles,
crockery, glass, mirror, and such into randomly shaped pieces. For more precise cutting of thick
materials like glass smalti or natural stone, a traditional mosaic hammer and hardie (also called a
bolster blade) may be preferred.
- Chopping Machine are a professional tool useful for high production.
- Glass Cutters are suitable for stained glass and mirror. Cutting curved shapes from these materials
is faster and easier.
For holding your sorted tesserae, mixing adhesives and grouts, adding color to grouts,
and holding water for cleaning. Save those containers you were about to throw out! You may not want
to clean out that cement or grout container, so these "salvaged" containers can just be
tossed out when done.
Depend on personal choice and the adhesives. Trowels of different sizes and
types are useful for cement-based adhesives. (For small work) plastic spatulas, butter knives, and
palette knives work well. PVA and epoxy bases can be applied with plastic spreaders, old brushes,
straws, toothpicks, wooden sticks, etc.
Help push the grout over the mosaic and into the spaces between tesserae. They
need to be flexible so as not to scratch the surface. Plastic spatulas, squeegees, grout floats, or
even gloved hands will work.
Tools for Pushing and Prodding
Are handy for moving pieces into place and scraping out excess
mortar or grout. Wooden sticks, wooden scrapers, tweezers, dental probes, toothpicks, awls, wooden
clothes pins, pencils, and manicure tools are just some of the choices.
Safety Equipment must include.
Eye goggles to wear when cutting and breaking up your tesserae.
A dust mask or respirator to wear when mixing powdered grouts, adhesives, and cements.
Heavy duty gloves should be worn when breaking materials. Disposable or rubber gloves should be worn
when handling grouts, adhesives, and glues.
Always read and follow the safety instructions that come with the tools and materials used.
- Is what is pressed into the spaces between the tesserae in most mosaics (some are never
grouted). It unifies the design and strengthens the piece. Made like cement-based mortars (but with
a finer sand), grout comes in fine and coarse forms for filling narrow and wide gaps respectively.
Some contain polymers for added strength and flexibility.
- They come in neutral, white, gray shades,
black, and many assorted colors. Grout pigments or artists acrylics can be added to make a specific
Are needed for wiping off excess grout and general tidying up. Lint free rags,
sponges, and non-scratch nylon scouring pads are quite useful.
Lets Get Started
Surface Preparation: Base surfaces should be clean and dry. When applying a mosaic to surfaces
like wood or interior / exterior walls, scoring the surface will add "tooth" and improve
the adhesion of your tesserae. Use a sharp knife or similar tool to key the surface. Sealing will
also benefit surfaces like wood and terracotta. Use a diluted solution of PVA or similar acrylic
bonding agent and apply with a brush. It is essential to seal all surfaces for wood bases and it is
recommended for unglazed ceramic and terracotta.
Tesserae Preparation: All tesserae need to be clean and free of dirt, grease, and dust. Wash your
materials before breaking them into smaller pieces. Lightly soiled items can be cleaned with a damp
cloth. If the tesserae are attached to a mesh or paper, soak in warm water to remove the backing and
glue. Allow all pieces to dry thoroughly. Shells need to be soaked in water for several days
(changing the water daily), then allowed to dry out over several days. Pebbles need to be soaked
overnight and then rinsed until the water runs clear. Allow them several days to dry out as well.
Test Your Adhesive: READ THE LABEL! FOLLOW THE DIRECTIONS! It doesn't hurt to test its
performance on a small piece of the base material. Pay special attention to your choice of adhesive
for outdoor projects. Extreme heat and cold can create cracks allowing water to fill the voids -
this will destroy your work when the freezing temperatures come.
Designs and Patterns: Inspiration comes from everywhere: nature, cities, surfaces, feelings,
dreams, pattern books, magazines, and the list goes on. The choice is entirely up to you. You can go
from totally abstract to precisely planned. You may want to use (or modify) an existing pattern.
Sketching out a basic cartoon can help you to solidify your idea, as well as to plan for color and
movement. You can draw guidelines directly on the base for reference. You may want to transfer
complex designs to wood or terracotta bases using carbon paper. Large designs can be transferred
section by section. Do what makes you feel comfortable, but don't over plan! Some spontaneity is
needed to make your design dynamic and interesting.
Color: Once you have a design, you will need to fill it with color. Choose what you like! Layout
your tesserae and play with different combinations. Lay them on your design to see how they work and
look. Keep in mind that each unit is a unit of color, texture, size, form and brilliance. How they
play off each other will affect your design. Remember that the viewers eye will mix the shapes and
colors in your design. Instead of covering a large area with the same tile, vary the shades used to
add interest (unless the effect you want is a uniform block of color!). Grade (transition) colors
into each other by varying the size and shape as they meet each other. Mix pieces of differing
colors together. Place opposite colors next to each other for contrast. Make black or gray lines to
accent or separate design elements or colors. Take advantage of patterns and colors in your
tesserae. Play, experiment, stand back, look, rearrange, change, stand back, look... - until you are
satisfied. Again, do what you like and once you get started don't be afraid to change or deviate as
the project unfolds.
Cutting the Tesserae: With any new technique or tool it is a good idea to practice on scrap
materials (before you attack that one piece of really unique china you have). Work in a protected,
covered, easy to clean area; you'll be creating shards and stray pieces that can cut the
unsuspecting visitor. WEAR SAFETY GOGGLES! You can cut all your pieces ahead of time and lay them
out on your cartoon or base; or you can work on the fly - cutting and fixing as you go. The choice
is yours and depends on the complexity of the design, shape of the base, and the adhesive used.
Mosaic Nippers: Hold the nippers with the end of the handles in the palm of your cutting hand and
the rounded end of the jaws facing towards you. Using the thumb and forefinger of your other hand to
feed the tesserae (face up) into the jaws about ¼" (6mm), squeeze the handles together while
you press your thumb and forefinger together. Applying equal and opposite pressure will create a
straight break. Make diagonal lines by angling the nipper head and aligning your finger and thumb
with this direction. Cut curves by removing small bits until you achieve the curve desired. Concave
cuts are possible by modifying the applied pressure and a bit of practice!
Tile Cutters: Place the tile on a flat surface and use the cutting wheel to run a score (line) from
edge to edge. Center the flared anvil above the score and squeeze the handles gently. If all goes
well you will get a clean break along the score line.
Hammer: An ordinary hammer is useful for breaking large pieces or those too thick or too tough for
nippers. Hammers are an excellent way to achieve random pieces. To contain the mess, place your
pieces in a heavy towel or in a paper or plastic bag before striking.
Traditional Hammer and Hardie: The hardie needs to be secured at a height which is comfortable for
your working stance and with the chisel pointing up. Hold the hammer firmly but with a relaxed arm.
Hold the tesserae centered on the chisel tip with your thumb and forefinger. Swing the hammer down
from above, aiming to align the hammer tip with chisel tip of the hardie. Swing gently! Too strong a
swing will cause the tesserae to break more erratically. Only swing as forcefully as you need to.
Practice makes perfect.
Glass Nippers: Used similarly to mosaic nippers. Align the wheel with the direction of the cut you
want and squeeze. Changing the angle and amount of pressure will create differing curves and pattern
Glass Cutter: Hold the cutter in your favored hand and place the cutter wheel on the glass about
1/8" (3mm) in from the edge closest to you. Place the thumb of your other (guide) hand behind
the cutter head to prevent it from rolling back. Apply a firm, constant pressure straight down
through the cutter onto the glass and roll the cutter wheel away from you all the way across the
surface of the glass.
Breaking with Hands: Form both hands into fists and place the glass between your thumbs and index
fingers with the score line between your thumbs. Your fingers should be clenched underneath the
glass with knuckles touching. Hold the glass firmly at the end of the score. With a quick even snap
pull outward and roll your knuckles by spreading your thumbs apart to break along the score.
With Breaker-Grozier Pliers: Form one hand into a fist, placing the glass between your thumb and
index finger close to the score line. Position the flat jaw of the breaker-grozier pliers on the top
side of the glass with the jaw parallel to the score and as close to the end of the score as
possible. Hold the glass firmly in your hand and apply quick, even pressure by first pulling
outward, then snap down with the pliers.
Applying the Design
Cementing: Mix your cement according to manufacturer's instructions. You are aiming for a
consistency like cake batter or heavy mud. Spread the cement onto a small area of your base using a
spatula or notched trowel. The thickness depends on the thickness of the tesserae. You want the
cement to grab the piece yet leave enough open space between pieces for the grout. You don't want it
to ooze above the finished surface of the mosaic. Press the tesserae into the cement until you have
filled this area, then repeat the process. You can also "butter" the tesserae (instead)
using a small trowel or palette knife. This works for larger pieces or if the cement base is not
quite thick enough. It isn't really suitable for small tesserae.
Mosaics Without Grout: Shells and stones are too textural and porous for grout; mosaics having
tesserae with a wide range of thickness; and some types like smalti and vitreous glass tiles fit so
tightly together that grout is unnecessary. For shells and stones, a cement based mortar is
recommended. For scallop-type shells you will need to
"butter" and fill the concave underside with cement mortar before placing them.
For glass tiles and smalti, you can use either an acrylic-based or cement-based mortar.
Color can be added to the mortar mix to suit your design (remember, you will have no grout to add
color to your design, so your only chance for added color is here). Apply the mortar to the base,
the thickness dependent on the tesserae used. Stones and
pebbles can be pushed in at the angle desired, fitting them snugly. The cement will ooze up between
them and become self grouting. If your tesserae are widely different in thickness, lay a thick
mortar base and push the tiles in only to the desired level.
Grouting is the technique of filling in the spaces between your tesserae. Generally, it is
desirable to make the grout level with the overall height of the mosaic surface. Grout is just a
fine textured version of cement mortar. It unifies the design. Its color enhances the design: and it
- The choices of grout color are endless. There are colored sands and premixed grout
colors. You can make your own by adding grout pigments or artists acrylics to your colored sand or
white grout mix.
Allow the cement to properly cure according to the manufacturer's recommendations. This will be at
least 24 hours for indoor mosaics, 72 hours for outdoor mosaics.
Mix grout according to the manufacturer's directions following all safety precautions. Add color
until you achieve the shade desired noting that it will be slightly lighter when dried. If you are
not sure of the color, test it using the piece you used earlier to test the adhesive, or test on a
small inconspicuous spot on the actual mosaic piece. You don't have to use the same color throughout
Scrape out any excess mortar between your pieces.
Put on some gloves and spread the grout on the surface using a plastic spatula, squeegee or your
hand. Make sure to push the grout down into all spaces and cover the entire mosaic
The grout needs to partially set before you remove the excess. Refer to the manufacturer's
instructions, generally about 15-20 minutes.
Use a clean, lint free cloth or a damp sponge to wipe off excess grout. Be careful not to dig into
the grout spaces pulling it out.
Once you have removed the excess grout you will have a haze over the surface. Buff it off using a
clean lint free cloth or crumpled newspaper. If you have specks of grout stuck to your tesserae
remove them using a non-scratch nylon scouring pad, wooden stick, or similar tool that won't scratch
Some materials and applications benefit from an application of sealant after the grout
is dried and cured. Sealing pebbles brings out their true 'wet' color. Porous materials benefit from
sealing also. Sealers are available in a matt or shiny finish. Read the bottle to see if it fits
Now, stand back and admire your handiwork!
There are variations on the technique presented here and many excellent book resources (see
below) to help you expand your knowledge and creativity. As you experiment and work with different
materials you will discover what methods, tools, and supplies work best for you!
Books and Article Resources
by Roger Ling Paperback
|Princeton University Press
Paperback / 1998 / 144pp
|The Art of Mosaics
by Joaquim Chavarria
Paperback / 1999 / 160 pp
|The Art of Mosaic Design: A Collection of
by J.Locktov - L.P.Clagett
Hardcover / 1998
by Connie Sheerin
Hardcover & Paperback / 2001 / 128 pp
by Elaine M Goodwin
|Trafalgar Square Publishing Ltd.
Hardcover / 2000 / 144 pp
|Encyclopedia of Mosaic Techniques (Encyclopedia
of Art Techniques)
by Emma Biggs
Hardcover / 1999 / 160 pp
by Leslie Dierks
|Sterling Publishing Co.
Hardcover / 1998 / 128 pp
by Kaffe Fassett & Candace Bahouth
|Taunton Books & Videos
Hardcover / 1999 / 160 pp
|The Mosaic Book : Ideas, Projects and Techniques
by Peggy Vance, Celia Goodrich-Clarke
|Trafalgar Square Publishing Ltd.
Paperback / 1996 / 128 pp
|Mosaic Workshop : A Guide to Designing and
by Emma Biggs, Tessa Hunkin
|Trafalgar Square Publishing, Ltd.
Hardcover / 1999 / 128 pp