Gold Leaf

(Trial 1)
Name: Njeri Ndungu, Teresa Soley, Lila Goldenberg
Date and Time:

2016. March.24, 4:00 pm

Location: Chandler 260
Subject: Application of Bole Layer

In order to practice the process of applying gold leaf and to produce gilded surfaces upon which to apply varnish for later experiments, we applied the bole layers for gilding as outlined in the following recipe and experimental protocol, taken from Marjolijn Making and Knowing Visit reproduced here:

Compare to recipes for gilding in BnF Ms Fr 640 See:
Practical gilding by Peter and Ann McTaggart ­
Materials
● gold and perhaps also silver
● gilder’s cushion
● gilder’s tip
● burnisher (agate)
● gilder’s brush for removing excess gold/silver
● we can gild directly onto our smooth gesso grounds, but painters would have commonly applied a red bole ground layer (red bole + rsg in various layers made smooth)

Recipe red bole
Grind red clay with water until it is a viscous paste. Now mix with rsg water solution (1:15). Apply with soft (minnever for instance) brush. Apply about four layers smoothly. polish last layer with your agate burnisher until shiny and very smooth

Experiment
First Trial:

Because the red bole recipe suggests using a 1:15 rabbit skin glue solution and the glue that we produced this year was 1:10 we made the decision to use the glue that had been saved from the last semester produced on [Find actual date of production]. It was preserved in the small fridge in a beaker covered with plastic wrap with rubber bands used to secure it.

• Two quarter sized mounds of bole were places on the water glass plate
• Tap water was added to the bole and mixed together with muller until it reached the following consistency
• 
• The resulting paste was transfered to a 100ml beaker
• 
• The rabbit skin glue was then placed in a pot filled with tap water on the the hot plate, suspended above the surface of the pot on a mason jar lid rim (standard double boiler set up)
• 
• The rabbit skin glue was reheated in double boiler for 7 minutes until temperature was brought up to 60 degrees celsius
• Two pipettes of rsg were added to the bole-water mixture and stirred with palette knife
• The resulting mixture was quite clumpy and inconsistent. More rsg was poured into the mixture.
• 
• The result of adding more rsg was that the mixture was too aqueous and the thick clumps were still present
• 
• The rsg was removed from the boiler when the temperature reached 70 degrees celsius
• The beaker with the bole mixture was dipped into the hot water in an attempt to reheat rsg and make the mixture more consistent
• 
• There was little change in the mixture's consistency and the trial was aborted

Results/ Reflections

• The bole produced was far too thick and inconsistent, containing many clumps of clay, to be used as panel preparation. We decided to dispose of the bole and instead try again.
• Perhaps the rabbit skin glue that we used was a bit too old, making it adhere in unpredictable and inconsistent ways. The container in which it was held was not well sealed and perhaps other items in the fridge contaminated it or just exposure to the relatively open conditions had adverse effects
• We also waited quite a while after the bole-water mixture had been produced to add the rsg. We only began reheating the rsg once bole-water mixture was complete. Perhaps the mixture had dried during the 7 minutes used to reheat the mixture and so the final bole we produced was primarily the clay-rsg rather than clay-water- rsg and this produced an undesirable final produce
• We plan on trying again with the rsg produced this semester and adding the rsg immediately after bringing the bole-water mixture to the proper consistency
• We should take better documentary photographs in order to get a better sense of what goes wrong next trial

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Name: Njeri Ndungu, Teresa Soley
Date and Time:

2016.March.28, 11:27 pm

Location: Chandler 260
Subject: Application of Bole Layer, Trial 2

Procedure


Materials

• 1:10 Rabbit Skin Glue solution
• Double boiler set up
• Thermometer
• Red Bole
• Glass plate and muller
• Palette knife
• ½ inch flat head paint brush
• 100ml glass beaker
• Tin can for hot water bath
• Gessoed Panel #3

• 
• Set up double boiler with 1:10 rabbit skin glue suspended in pot filled with water on top of mason jar lid.
• Placed the thermometer onto gelatinous rsg layer and watched closely

• 
• Placed two palette knife scoops of bole onto the ‘water’ glass plate
  • Is there a more efficient way of measuring the amount of pigment used? Accuracy vs efficient use of time
  • In the end it turned out to be quite a bit more bole than we needed

• 
• Added two pipettes full of water to bole and grind with muller
  • The mixture is quite sticky and had to periodically scrape the muller clean
  • Attempt to thoroughly incorporate water before adding more
• Added two more pipettes of water

• 
• Checked the temperature of the glue. It was 53 C

• 
• Added three pipettes of rsg to the bole-water mixture on the glass plate
  • The rsg this time (1:10) was much less viscous than the 1:15 used during the last trial
• Began mulling in figure 8 motion

• 
• Periodically gathered bole together with side of palette knife into small pile to grind all thoroughly
  • This texture was much smoother and easier to handle than that produced with
• Transferred the final mixture to a 100ml glass beaker’

• 
• Used a half inch wide flat head brush to apply the bole to square 7D on Panel #3
  • Applied much like one applies paint
  • Applied in thin, inconsistent but relatively even layer

• 
• Used brush to apply bole to 6D
  • Applied as advised by Jenny and Marjolijn, avoiding the overlap of brushstrokes
  • Each brush stroke was quite thickly applied and naturally there was a bit of overlap between the strokes

• Waited 2 min for 7D to dry
• Applied second layer perpendicular to the first
• Waited 5 min for 6D to dry
• Applied second layer perpendicular to first

• 
• Placed glass beaker into a tin can filled with warm water to keep bole mixture from congealing and becoming too viscous to use

• 
• Waited 3 minutes for 7D layer 2 to dry
• Applied third layer perpendicular to the second
• Waited 6 minutes for 6D layer 2 to dry
• Applied third layer perpendicular to the second

• 
• Decided that we produce more squares with the bole mixture so that we could have more attempts with gold leaf and gold surfaces on which to test the varnishes produced
  • Applied layers perpendicular to each other waiting 2 minutes between each layer
  • These layers were applied in the ‘paint’ method used for 7D rather than the ‘strip’ method in 6D because it produced a smoother surface (perhaps this will end up undesirable when burnished or sanded if not thick enough application)

• 
• Waited 5 minutes to apply fourth and final layer of both 7D and 6D
• Allowed all bole layers to dry for 7 days - next will sand and burnish the surfaces before applying the gold leaf

Results and Reflection

• We mixed the RSG into the bole-water mixture on the plate. This allowed for us to get much of the inconsistencies originally encountered out of the mixture
• I have this strange habit of changing the tone/tense of my field notes, changing from a past tense record to a list of instructions aimed at the reader

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Name: Njeri Ndungu, Teresa Soley, Lila Goldenberg
Date and Time:

2016.April.8, 3:00 pm

Location: Chandler 260
Subject: Application of Gold Leaf

[Temporarily Having Difficulty Uploading Images to Wiki, will try again at 1pm]

Conditions of the room:
Temp: ~68-70 F, 20 -22 C
Air Quality: Humidifier on, Air conditioner on (erratic airflow)
Light: Late afternoon light from window, fluorescent lab lighting


Materials:

Panel 3 (Squares 6C- 6E and 7C - 7E prepared with bole)

Gold leaf

Water (tap)

Rabbit skin glue

Grain Alcohol (ethanol)

• Didn't really need newspaper since not much dust created. The sand paper was so fine.

• Used three styrofoam boards found in lab to create screen using masking tape

• Unclear when sanding is finished. Decide to go back with rougher grain sandpaper on difficult spots and then return with finer grade.
• 
  
• Sand paper got quite close to gesso layer - must use caution when burnishing
• Marjolijn says its okay to gold on gesso as long as it is smooth.
• Used cheese cloth to remove excess bole before burnishing.

• For sizing glue: used 30ml of water since rsg was likely more concentrated from reheating throughout the semester
• 
  
• The rsg was brought up to 57 C
• Put two drops of rsg in the alcohol and water and mixed with pipette tip.
• Wouldn't dissolve. Briefly suspended in hot water from double boiler and it quickly dissolved. Let sit in front of gilding screen for 20 minutes before use

• Agate burnisher very delicate. Don't put on table don't rub masking tape.
• Press down with first finger to add more pressure per square inch. Rub firmly. Becomes clearly more polished and very reflective.

• It's hard work to be a goldsmith. That grip strength must be cray cray.
• Occasionally rubs burnisher on the back of hand
• Get a pep talk from Jenny.
• Best to rest hand on chest according to Cennini

• Three squares burnished

• Had to fiddle quite a bit with the leaf. Kept getting folded on itself

• Gently press down to cut, on very slight sawing motion
• Lay out for one smooth move across. - arrange the opening of the gilders cushion and the square on the panel so there is not much complicated maneuvering involved

• Create static by rubbing on wrist or behind ear or across forehead

• Tap leaf lightly with gilders tip to lift the leaf

• Have someone else apply the sizing glue

• Smooth out with the brush to flatten. Just dab it with brush don't push.

• The gold becomes damaged very quickly. Is it the gold or the gilders brush is too rough

• The brush actually as residue of gold on the brush

• Go from the middle of the leaf with the knife. The sides of the leaf hangs quite significantly off of the side of the knife

• Try to put down one side then unfurl the knife underneath
• Don't straighten from above. It just causes the creases to flatten rather than unfurl
• You hold your breath unintentionally but that helps.
• Tapping the gold leaf with the brush damaged the gold immediately.
• Must be the quality of gold. Perhaps it's too thin?

• Jenny and Lila decide to try gilding on gessoed board with the starch glue to try it out before using it to gild on paper
• "The glue is very 'glooky'" according to Jenny - placed in a hot water bath to keep from coagulating
• It is very thick and in consistent (I didn't get any pictures of this, perhaps Lila has some?)
• This could technically be eaten since all ingredients are edible. Not very appetizing looking though. Thicker than it usually be so they did not do 6 layers

• Jenny mistakenly dropped a bit of size glue on the perfect leaf causing slight yellow discoloration
• To burnish it you want wait for it to be dry but not too dry.

• Attempted to burnish a little and it was not ready yet. Gold flakes were left on the burnisher

• Do tap test and listen to see if it is dry enough yet.
• Would their gold leaf have been this thin?

Final image of the Gold Leaves


Detail of the 'perfect' Gold Leaf

Results and Reflections:

• While the manuscript includes a very detailed recipe on gilding, we used the modified skill building method employed by the class last semester during skill building. However, perhaps it would be a good idea to go through his process to compare? We have the materials and perhaps this has a slightly different effect on the gold.
  • Njeri: The reason why people would make gold color is because laying gold is SOOO difficult.
  • Teresa: Can't imagine doing this process for an entire background.
  • Njeri: They are not little pieces either (or they don't look like small squares of leaf) so how did they do this with such large pieces or make the surface so seamless?
• Brief convo post gilding:
• So stressful you hold your breath, also this prevents you from stirring up wind. No amount of planning really prepares you for the transfer process. It feels like 90% luck, 10% air flow.
• I wonder if this was actually how difficult it would have been then since they obviously didn't have air conditioners (so the air probably didn't change so dramatically so often) and I can't imagine that they got the gold leaf this thin if they are simply hamming it out flat - (though when I was going through the gold recipes, there was one on gilding sword hilts that said that it should not use the same type of gold leaf as painters use because that gold leaf is too thin so perhaps it was fairly thin)

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ASPECTS TO KEEP IN MIND WHEN MAKING FIELD NOTES

• note time
• note (changing) conditions in the room
• note temperature of ingredients to be processed (e.g. cold from fridge, room temperature etc.)
• document materials, equipment, and processes in writing and with photographs
• notes on ingredients and equipment (where did you get them? issues of authenticity)
• note precisely the scales and temperatures you used (please indicate how you interpreted imprecise recipe instruction)
• see also our informal template for recipe reconstructions

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