Gilding a Byzantine icon

Betsy Porter
Art and Iconography
GILDING; GOLD LEAF OVER RED CLAY BOLE

PREPARING RED CLAY BOLE (pronounced like "bowl")

Prepare liquid bole in advance. This is a messy job, so wear an apron, and protect your counter top, or else
work outdoors.

Bole is finely ground clay or earth, consisting of tiny pieces of stone. It sinks in water, and can clog drains.
Select an outdoor location to discard wash water.

Tools: You will need a large dedicated porcelain mortar and pestle, 2 or more nesting fine-mesh strainers, 2
large (soup size) spoons, a piece of slick-surfaced white cardboard such as shirt cardboard, a large-mouth
container with a secure lid, and a dish pan partially filled with water.

To make enough liquid bole for 2 to 4 icons, mix one heaping spoonful of paste bole with one flat spoonful of
liquid hide glue, using mortar and pestle. Add a small amount of warm water, working the mixture as smooth as
possible, to the consistency of heavy cream. Let it settle a few minutes so coarser grains will settle to the
bottom.

Strain the mixture into its wide-mouth container. Use a spoon to scrape the liquid bole through two or more
nested fine-mesh strainers.

Apply a test sample to shirt cardboard, and let it dry completely. Test by scraping with fingernail. Clay should
show a light scratch mark. If clay can be scraped off easily, there is not enough glue. If the surface is overly
glossy and no mark is made, more paste bole is needed.

If necessary, return the mixture to the mortar, add glue or paste bole as required, and repeat the process.

When you are satisfied, place lid tightly onto container of liquid bole, put mixing tools into dish pan, and clean
up. Discard waste water outdoors, not down the sink drain! Clay bole can clog sink drains.

APPLYING GOLD LEAF

Gilding can be difficult In warm or dry weather. Put your icon in the
refrigerator for 5 to 10 minutes, no longer.

Now breathe closely on your icon, on the burnished bole where you want
to gild, using warm moist breath from the bottom of your lungs. Light
condensation should form on the spot where you breathe.

Quickly lay the gold leaf on the selected spot of polished bole, gold side
down and wax paper on top. Lay a piece of rouge paper over it. Press
and rub gently but firmly with a soft wide brush.

The condensation from your breath should cause the gold leaf to
adhere to the bole.

When the wax paper is removed, some gold leaf may extend past the
edge of the halo area. Don't brush it away! Use your soft brush to move
it carefully back onto the halo, and press down with the brush.

Use "scraps" of gold leaf, still sitting loosely on wax paper, to fill in gaps.
If there are small gaps where gold leaf won't stick, mix 2 drops of liquid
gum Arabic (from watercolor section of art supply store) with 2 drops
water, and paint lightly on the spot before applying gold leaf. After
several attempts at gilding with the same gold leaf, it will not come off of
the wax paper.

Save bits of loose gold leaf in a small lidded container, to be used later
for shell gold.

Repeat gilding for at least 2 layers of gold leaf. Using a soft wide brush,
brush the freshly applied gold in a radial pattern, center to edge, to
soften irregularities.

Gold leaf is soft and "touchy" when first applied. In a couple of hours,
after the gold leaf has stiffened, you can burnish all or part of it - in
which case any defects, bumps, bubbles, or low places in the bole under
burnished gold leaf will be visible. I prefer to leave it matte gold, or to
impress a design - often a very simple design such as a row of dots.

If the bole under your gold is exquisitely level and smooth (as mine
usually isn't), you can burnish the entire halo to a high gloss. Work
lightly, running the stone burnisher radially, center to edge of halo.

PREPARING GOLD LEAF

Gold leaf comes in books of 25 sheets, separated by orange "rouge paper"
which does not stick to gold. Buy 23 or 24 carat "water gilding" or "surface"
gold leaf - not "patent" gold leaf.

When working with gold leaf, close doors and windows to eliminate drafts.
Turn off incandescent desk lamps; the heat may warm your icon.

Cut ordinary wax paper into squares slightly larger than the gold leaf. When
you are ready for gilding, carefully open the book of gold leaf, quickly lay
down a piece of wax paper centered on the gold, and rub lightly all over.

The gold leaf should stick to the wax paper. Use dedicated sharp scissors
to cut the assembly into 6 to 8 pieces, each with a "tail" of wax paper for
handling. Rectangular or slightly wedged-shaped pieces may be used to fill
in a halo in a radial pattern. Or you may prefer to cut the edge of the gold
leaf to fit the curve of the halo.

Immediately return remaining gold leaf to its envelope. Do not pick up
another sheet of gold leaf until you have finished applying the first sheet.

APPLYING LIQUID BOLE TO YOUR ICON

On your icon, mark the edge of the halo, using a compass with pencil tip. The halo should be centered on the
head, around eyebrow level. (On many icon drawings, the center of the halo is marked with an X.) Leave at
least 3/8 inch (10mm) between the top of the halo and the edge of the board. See layout page.

Draw a light pencil guide line around the perimeter of your icon board, a scant 1/8 inch ( 2 to 3mm) from the
edge of the board.

In your palette cup, put a few drops of water. Coat a No. 2 round brush with honey, about half-way up the
brush, and mix the honey into the water. Now mix in liquid bole, and stir well. Later, the honey will help the gold
leaf adhere to the dried and burnished bole, even in dry weather.

Your bole mix should be very smooth, the consistency of heavy cream. If it seems at all gritty, let the grit settle
to the bottom, and use the top layer for areas to be gilded. Add another drop or two of water if needed.

Starting in one corner and keeping a wet edge, apply liquid bole to the halo area. Holding your brush at an
angle to the surface, apply evenly and carefully with a fairly full brush, using small circular brush strokes.
Do not use long straight brush strokes! Your brush should barely touch the surface of the board. Liquid bole
should form a thick puddle and level off smooth and flat under its own surface tension. White
surface should not show through bole. You should not need a second coat. One of my students has
compared this process to applying icing on top of a cake, without letting the spreader touch the cake.

If bubbles develop in the bole puddle, gently work them out with your brush.

Slight irregularities in the edge are normal. If you make a big mistake, clean it gently with a damp Q-tip. Do not
scrub. It's OK if a slight stain remains.

Now paint the edges of the icon with more liquid bole; honey not required. Raise the icon up on a support
slightly smaller than the icon, such as a plastic palette or an old magazine. Use your No. 2 brush to paint in
from the edge to the pencil line. Now use a large flat brush to paint the vertical edges. Long strokes are OK
here. Check that no white spots remain! The edges usually require a second coat. Let bole dry.

SANDING AND BURNISHING DRIED BOLE

To receive gold leaf, the dry bole must be sanded and then burnished to a smooth near-mirror finish.

Use increasingly fine sandpaper or other sanding media to smooth out the bole; first 320 grit, then 400 grit,
then 600 grit. Remove bumps and level out dents, checking occasionally under bright light to locate any
remaining irregularities or holes in the surface. Wipe up dust with a tissue - don't blow it around.

Be careful not to grind all the way down to the white gesso. On a sculpted board with a recess, be careful at
the edge of the recess! As long as some bole remains on the surface, gold leaf should adhere to the bole.

Now burnish to a sheen, using a smooth metal or hard stone burnishing tool. A tumbled hard stone, perfectly
smooth with no cracks or pits, also makes a good burnisher. Use firm but light pressure, just enough to leave a
shiny track on the hardened bole.

Burnish systematically, because the burnish marks will show through the gold leaf. Burnish radially from center
to edges of halo, so that all burnish lines point toward the center. Also burnish around the edges, where bole
meets the white gesso of the board. Insofar as possible, avoid burnishing the white gesso.

Should you sand and burnish the bole on the edge of the board? You may if you wish, but it's optional. Like
almost everything in iconography, there's a symbolic meaning. The edge represents our everyday life and our
outer persona, which are inevitably imperfect and subject to rough treatment. The inner recess or "ark" of a
sculpted board, where the holy images appear, is like our subconscious, or a dream state, or our inner self.
But some of the "heavenly" gold extends beyond this inner recess, into the bordering area.

Gold leaf applied over bole provides a slightly
raised, attractively dimensional halo.

At a class or workshop, liquid bole and gold leaf are
usually available for classroom use. There may be an
additional charge for gold leaf. Although gold is always
expensive, the gold leaf so thin you can see the light
through it! It represents only a small proportion of your
expense for art supplies.

IMPRESSING A DESIGN IN THE GOLD LEAF (OPTIONAL)

This process produces a really beautiful dimensional effect, and it’s great for concealing bubbles and
defects in the bole – but it must be done while the gold leaf is fresh, one to 30 hours after application.
After that, the gold leaf stiffens. Allow 3 hours work time.

Use a pencil-tipped compass to lightly draw a single or double line around the perimeter of the halo, 1/8 inch
to 3/16 inch in from the edge. This border should remain without a design.

Select a design. A cross in the halo indicates Christ, or a symbolic representation of Christ. An eight-pointed
star indicates divinity. Floral, leafy, radiating, or abstract designs may be used for any saint, prophet, or
angel. Use a printed pattern, use a ruler or drafting template, or work freehand.

Personally, I find that printed halo patterns are rarely a good fit for my icon. I prefer to make leafy or floral
patterns freehand, directly on the gold leaf. Lightly draw a curly leaf, then another and another, until the
space is filled. If empty spots remain, put in a small flower, or an oval or round shape. You can find other
ideas in illustrated books and on china plates. As always when trying something new, practice on paper first.

If using a printed halo pattern, Xerox to slightly smaller than the size of your saint's halo. Using tracing paper
and your paper icon pattern, adjust the design to fit your saint's halo. Tape tracing paper over the gilded
halo, and trace over design with ball-point pen. Light lines will show on gold leaf.

Work with care, because mistakes cannot be undone.

Use a round-tipped metal craft tool or a “dead” ball-point pen, first to make closely spaced regular
impressions around the perimeter line, then to delineate the pattern.

For a floral or leafy design, stipple the background with many small impressions, and leave the designs
without stippling. Optionally, parts of the design may be burnished. You have three basic textures from which
to choose; stippled gold, matte gold, and burnished gold.

For larger-scale designs, hammer in impressions with small leather-working tools or nail sets.

Picking up gold leaf on
wax paper, and cutting into
smaller wedges for easier
handling. Always leave a
"tail" of wax paper.

Breathe on the bole with warm
moist breath, and immediately lay
down the wax paper with gold leaf.
Brush or press into place, using
rouge paper over the wax paper.

When gilding is complete, your icon is ready for the red halo circle,
applied with a ruling pen compass, followed by the first layers of
paint, known as roskrish or roskrysh.

Forward to Studio Tips including use of the ruling pen

Forward to Shell Gold - applying gold leaf over paint

Back to Home Page

Back to Main Technical Page

Yoshi Mathias applies gold leaf over bole,
using a soft brush. She protects the gold
leaf with rouge paper. Loose scraps of
gold leaf go into the small plastic yogurt
container in the foreground.

GOLD LEAF WILL STICK TO PAINT!

COMPLETE GILDING BEFORE YOU
START PAINTING.

After painting, you can make minor
repairs to gold leaf, but patches
will show slightly.

The application of gold leaf over clay bole is full of symbolic meaning!

With the gold leaf, you "breathe life" into the clay, as God breathed life into Adam.

Just as raw clay is fired into a handsome and durable pot, applying gold leaf "fires"
the clay bole into luminous beauty, reflecting earthly and heavenly light.

The halo images the solar disc, and earthy clay is raised to a likeness of heaven.

NOTE: Gilding is beautiful but not essential. Many historic icons have a painted halo -
usually light yellow, but sometime bright red or emerald green! If you are starting off, or
have difficulty obtaining bole and gold leaf, paint the halo instead. Coat the edge of your
board with reddish brown paint instead of liquid bole. Alternatively, you can use "patent"
gold leaf applied with adhesive, which results in a relatively flat look. Modern adhesives are
antithetical to the Prosopon method, which relies on use of natural materials only.