Betsy Porter

Betsy Porter
Art and Iconography

Gilding; Gold Leaf Over Red Clay Bole

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.

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

The clay symbolizes the earth from which Adam (and all humanity) was created. 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 sometimes 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 and cannot be burnished. Modern adhesives are antithetical to the Prosopon method, which relies on use of natural materials only.

PREPARING RED CLAY BOLE (pronounced "bowl") - or buy prepared liquid bole.

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 mixed with animal skin glue. It sinks in water, and can clog drains. Select an outdoor location to discard wash water.

The binder for liquid bole is animal-skin glue. Without glue binder, bole will not stick properly to the board.

Tools: You will need a large dedicated porcelain mortar and pestle, 2 or more nesting fine-mesh strainers plus optional piece of nylon panty hose, 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. (Some iconographers use dried powdered bole.) Add a small amount of warm water, working the mixture as smooth as possible, to the consistency of heavy cream. Let it sit 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. For smoother bole, line strainer with a piece of nylon panty hose.

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.

Start applying bole in one corner, outlining the edge of the halo as you go. Fill in between the edges with a wet brush held at a slant, to make a puddle of bole, which should level out smooth under its own surface tension. If the bole on the board gets bumpy, add a drop of water to the bole in the palette. Keep a wet edge, and work fairly rapidly. Proceed until halo area is covered.

Applying Liquid Bole To Your Icon

On your icon, lightly 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.
Optional: Engrave lightly around area to be gilded - around edge of halo, and between the figure and its halo.

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.

(Here's a suggestion I haven't tried yet; prime-paint areas to be gilded, using 15 drops vodka to one drop hide glue. Let it dry before applying bole. This is supposed to reduce bubbles in the bole.)

If using paste bole prepared according to instructions above - 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.

Stir your bole mix slowly and gently, so as not to form bubbles in it. 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 to be bole in the palette if needed.

If using prepared liquid bole - Stir well, to mix the liquid at the top with the heavy material at the bottom of the jar. Spoon or pour some bole into your palette cup. Coat a No. 2 round brush with honey, about half-way up the brush, and mix the honey into the liquid bole. The prepared bole is quite fluid and usually requires no additional water. (Prepared liquid bole makes a nice smooth surface for gilding; but tends to run down vertical surfaces like the sides of the board, and diagonal surfaces like the slope at the edge of the recess or kovcheg. I like to have both liquid and paste bole available for these different uses; or better yet to mix them.)

Optional for experienced iconographers: Once you have mastered the ruling pen, you can fill it with liquid bole and use it to neatly define the edge of the halo.

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, mop on evenly and carefully with a fairly full brush, using small circular brush strokes. Do not use long straight brush strokes! Do not dab! Your brush should barely touch the surface of the board, but should not leave the board until the brush needs to be refilled. 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. Immediately add more bole to any thin spots. 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. This thick puddle of bole will usually take an hour or longer to dry.

Bubbles in bole can be a problem. If bubbles develop in the bole puddle, gently work them out with your brush, or try blowing on them softly through a drinking straw.

Slight irregularities at the edge, where the bole meets the board, 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. You may want to add a little more glue to reduce future chipping of the edge. Raise the icon up on a support slightly smaller than the icon, such as a stack of plastic palettes or magazines. Use your No. 2 brush to paint in from the edge 2-3mm 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 - which may take an hour or so. 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 (if needed), then 400 grit, then 600 and finer 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 cautious 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. If you see grooves or dents, lighten the pressure. Many iconographers prefer to polish with a small piece of horsehair cloth interfacing, available at some fabric stores.

The burnished bole may have a slight orange peel texture, especially with prepared liquid bole, indicating that the clay grains are thicker than the dried liquid. In most cases this is OK; but if in doubt, make a small gilded test patch. If the orange peel texture keeps gold leaf from adhering, apply a second layer of 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 (kovcheg or "ark") of a sculpted board, where the holy images appear, is like the subconscious, or a dream state, or our inner self. But some of the "heavenly" gold extends beyond this inner recess, into the bordering area.

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 (if needed), then 400 grit, then 600 and finer 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 cautious 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. If you see grooves or dents, lighten the pressure. Many iconographers prefer to polish with a small piece of horsehair cloth interfacing, available at some fabric stores.

The burnished bole may have a slight orange peel texture, especially with prepared liquid bole, indicating that the clay grains are thicker than the dried liquid. In most cases this is OK; but if in doubt, make a small gilded test patch. If the orange peel texture keeps gold leaf from adhering, apply a second layer of 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 (kovcheg or "ark") of a sculpted board, where the holy images appear, is like the subconscious, or a dream state, or our inner self. But some of the "heavenly" gold extends beyond this inner recess, into the bordering area.

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. "Double" weight is preferred.

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.

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

Applying Gold Leaf

Gilding is highly sensitive to temperature and humidity. If possible, gild early on a cool morning, when condensation forms on car windshields. Gilding can be difficult In warm or dry weather. Put your icon in the refrigerator for 5 to 10 minutes. A large heavy board may require more fridge time. The cooling should help the moisture in your breath condense on the clay bole. If gold leaf sticks to the white gesso, the board may be too cold.

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 square of rouge paper over it. Press and rub gently but firmly with fingers and/or 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. Vodka can be used similarly. 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, such as a small plastic yogurt container, to be used later for shell gold.

Repeat gilding for at least 2 layers of gold leaf. The second layer may be applied immediately after the first. Using a dry, soft, wide brush, brush the freshly applied gold in a radial pattern, center to edge, to soften irregularities. The gold will take on a smooth satin sheen.

Gold leaf is soft and "touchy" when first applied. In an hour or two, 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 satin 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.

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.

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.

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 gradually 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 geometrical designs may be used for any saint, prophet, or angel. Use a printed pattern, use a ruler or drafting tools and templates, 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. When paper is lifted, 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 indentations around the perimeter line, then to delineate the pattern.

For a floral or leafy design, stipple the background with many small indentations, 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, satin or matte gold, and burnished gold.

Some designs repeat at equal intervals, in a radial pattern around the halo. Divide the halo into equal wedges using a protractor.

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

As you work on your design, pinholes may open up. At left, a half-completed freehand leafy design has exposed many spots of bole. There are 7 five-petaled flowers among the leaves - and I hammered in five closely spaced impressions at the center of each flower, using a small nail set. This turned out to be a technical error - the gold leaf peeled off the heavily textured centers of the flowers.

After the design was completed, I applied another layer of gold leaf, which covered most of the pinholes. Then I "stippled" the entire halo with a soft dry brush held vertically, and the design came right through the new gold leaf. But I could not persuade the gold leaf to stick to the centers of the flowers. So, during the painting of the red halo line, each flower received a spot of red paint in its center. Although the spacing is irregular, the effect pleases me.

A GILDED BACKGROUND can be gorgeous!

Many historic icons have gilded backgrounds, because the intense brilliance of gold recalls the light of heaven.

A gilded background requires many hours of work; not recommended for beginners. Wait until you are confident of your gilding skills!

For this 13 x 17 inch icon, I used an extra layer of prepared bole for additional dimensionality in the halo areas. Layout, application of bole, sanding and polishing, and gilding took about 15 hours. 27 sheets of gold leaf were required.

For a neater edge, before applying bole, engrave the lines where gold leaf will meet the white gesso. This is especially helpful for the straight lines on the thick border of the board, surrounding the rectangular recess.

OTHER METHODS OF "WATER GILDING" OVER BOLE - Gold leaf can be adhered to bole by first lightly brushing the surface of the bole with plain water, or water with a few drops of gum arabic, or vodka.

I have not tried any of these methods, but experimentation on practice board (not on your icon) is encouraged. Many of Loretta Hoffmann's icons have beautiful smooth gilded backgrounds, achieved by brushing vodka over the bole. She says she also uses lots of gold leaf.

For more information about gold leaf, and the tools and methods by which it can be applied, go to www.auricgold.com. Or call Easy Leaf Products 800-569-5323.

Laurence Farhat has laid out his icon of Christ Enthroned, and now it is ready for gilding.

When gilding is complete, your icon is ready for the red halo circle, either painted over guide lines, or applied with a ruling pen compass. This will be 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

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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.

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