Safety and Workflow
"Imitation Jasper"

Annotation: Imitating raw nature

Participants: Isabella Lores-Chavez and Charles Kang

Materials Needed:

• Horn (water buffalo from India, 5-6mm thick) - 2 sheets available
• Clear turpentine
  • Could also use spike lavender varnish (NOT in lab inventory)
• Spike lavender oil - available, either from Chelsea Studios (10 mL) or Kremer (250 mL)
• Yarn - 100% wool, undyed, 10 grams available from Catskills Merino Sheep
  • To be dyed at least two different colors
  • Pigments for dyeing yarn (red madder, weld)
• Pigments to be mixed with clear turpentine and/or lavender varnish
  • Verdigris?
  • Red madder?
• Gold leaf - 30 leaves available from Mona Lisa Art Products
• Silver leaf - 14 leaves available from GLF Pure Genuine Silfer Argent Pur
• Distilled water for dyeing yarn
• Some kind of adhesive for applying yarn to horn
• Extraneous (from marginal note for inlaying beds with imitation jasper)
  • Gum amoniacum - not in lab inventory
  • Vinegar
  • Talc (chemical formula H2Mg3(SiO3)4) - not in lab inventory

Tools Needed:

• Brushes of various sizes
• Sharp metal tool for scraping
• Ceramic plates for laying out the painted horn sheets
• For mixing pigments and turpentine:Beakers for dyeing yarn
  • Muller
  • Palette knife
  • Ceramic plates
  • Plastic pipettes
• Beakers for dyeing yarn
• Hotplate for dyeing yarn

Workstation Setup:

• Plenty of clear counter space
• Turpentine colors set up directly besides horn sheets for painting
• For dyeing yarn:
  • Basic hotplate for heating distilled water in a beaker
  • Pre-cut strings of yarn for dyeing
  • Potash alum
  • Pigments for dyeing yarn
  • Polyester netting for pigments

PPE:

• Lab coat
• Safety glasses
• Nitrile gloves

Outline of Experiment:
Four main steps

1. Painting thin sheets of horn

• We must make colors with a turpentine base. What pigments can we use for this?
• We can additionally make colors using spike lavender varnish, the alternative the author practitioner gives to turpentine. We can try samples of horn using paints made of both turpentine and spike lavender varnish.
• In either case, the paint must be rather translucent: the recipe says that "matte, opaque colours are not appropriate, no matter how fine they are." This suggests that the quality of the paint (whether made of a turpentine or spike lavender varnish base) matters less than the opacity of the glaze.
• The question remains: how many layers of color to apply?After painting, we will set the sheets of horn to dry. For now, we will assume that the paint must be completely dry before we move on to the application of the dyed yarn.
  • For now, the objective will be to paint the horn enough that the natural color of the horn is no longer dominant. However, we want to make sure that the glazes do not obscure the "lustre and [...] fatty polish" that makes the horn so suited to imitating jasper, according to the author-practitioner.
  • Furthermore, do we apply multiple colors to a single sheet of horn? We could try a few variations: a sheet painted a single color and a sheet painted with a combination of colors.
    • Given that we may want to try out using colors with BOTH turpentine and spike lavender varnish as a base, we may need to acquire more thin sheets of horn, to have at least four to work with.

2. Dyeing yarn (various colors)
Field Notes for Dyeing Yarn

• We will follow Jo Kirby's recipes for dyeing yarn, as they are the result of historical investigation into (as well as actual experimentation with) pigments and dyeing techniques from the early modern period.
• The recipe calls for "heavy yarn" ("des laines a gros poil"). In the efforts to use a material with the right thickness that would more likely have been available in France in the late sixteenth century, we will use the 100% wool yarn rather than the alpaca yarn.
• Cut up the yarn into lengths 1.5 to 2 times the length of the sheet of horn. This would make it long enough to apply it to the sheet of horn in a winding pattern, but not so long that a single length of yarn would overwhelm the surface of the horn sheet. We should have about 8-16 lengths of yarn dyed: at least one of each of the two colors, to be applied (potentially) to four different sheets of horn.
• Dye the yarn at least two different colors in a beaker on a hot plate.
• Pigments for dyeing yarn: weld (yellow) and madder (red).
• Once the yarn has been dyed, set out to dry. The goal will be to apply it to the painted horn sheets only when it is completely dry.
  • Do we need to wash it? Will this change the color saturation? Will setting it out to dry alone change the color saturation as well?

3. Applying yarn to horn and scraping

• We will have dyed yarn at least two different colors. Since we will be working with horn sheets painted in a variety of ways, we will want to try out the yarn in several combinations.
  • Horn sheet painted red + red yarn
  • Horn sheet painted red + red yarn + yellow yarn
  • Horn sheet painted green + yellow yarn
  • Horn sheet painted green + red yarn + yellow yarn
  • Horn sheet painted red and green + red yarn + yellow yarn
• What can we use to adhere the yarn to the horn sheets?Once the dyed yarn has been intermingled on the surface of the horn sheet, we will try scraping oblique lines into the surface of the horn through the yarn.
  • Animal glue?
• We will also ideally have enough sheets of horn to try a set without the dyed yarn applied. For these sheets, we will scrape directly into the colored surface, making oblique lines moving in the same direction (not intersecting), which seems to make the most sense based on patterns visible in real jasper stone.

4. Applying silver and gold leaf

• The recipe specifically recommends using silver or tin leaf for horn embellished with colors made of turpentine. For the horn sheets painted with turpentine colors, we will apply a silver leaf backing.
• If we choose to paint horn with colors made of spike lavender varnish, we will use a gold leaf backing for these sheets.
• What part of the product does "backing" refer to? If we apply heavy dyed yarn to the horn, what is the silver or gold leaf applied to? Does this part of the recipe only apply to sheets of horn that have not been embellished with dyed yarn?

MATERIAL 1: Bovine horn
Hazard statements from MSDSs for Various Materials:

• No existing MSDS.
• We will not be inducing any physical transformation and will not be subjecting the horn itself to extreme heating or cooling. We will also not be altering its physical state to produce any kind of dust or excretion from the material.

Safety Precautions:

• In the even that we try to cut the horn ourselves, we will have to evaluate what tools we could use and how feasible it would be to do this ourselves.

Waste Management Plan:

• We do not anticipate producing waste from this material, as we will use units of it in their entirety.

MATERIAL 2: Spike lavender oil
Hazard statements from MSDSs for Various Materials:

• Mild health hazard and hazard to the environment.
• Toxicity and Chronic level 2 (moderate).
• Can cause skin and eye irritation as well as respiratory irritation.

Safety Precautions:

• Should be used in a well-ventilated area. When using, avoid breathing vapors.
• NOT to be ingested.
• Wash hands with soap and water after handling.
• Avoid personal contact.

Waste Management Plan:

• Suitable container is a metal can, clearly labelled.
• Avoid oxidising agents, acids, acid chlorides, acid anhydrides, and chloroformates.
• Cannot be discarded directly into sewer or waterways.

MATERIAL 3: Venice turpentine
Hazard statements from MSDSs for Various Materials:

Safety Precautions:

Waste Management Plan


MATERIAL 4: Gold leaf (gold)
Hazard statements from MSDSs for Various Materials:

• Toxicity of 1, Reactivity of 2.
• No specified hazard statements.

Safety Precautions:

• Avoid contact with skin and eyes.
• Avoid ingestion and inhalation.
• Avoid generating dust.
• Can react with acid to produce flammable / explosive hydrogen gas.

Waste Management Plan:

• Store in cool, dry, well-ventilated area.
• Can be stored in polyethylene or polypropylene container.
• Do not allow wash water from cleaning or process equipment to enter drains.

MATERIAL 5: Silver leaf
Hazard statements from MSDSs for Various Materials:

• No existing MSDS.
• We will be using silver leaf in the prepackaged units already in lab inventory.

Safety Precautions:

• Avoid contact with skin and eyes.
• Avoid ingestion and inhalation.
• Avoid generating dust.

Waste Management Plan:

• Do not allow wash water from cleaning or process equipment to enter drains.
• Remaining material to be returned to existing storage, unless it has come into contact with other materials, in which case it should be disposed of in solid waste containers in lab.