[Verdigris]

Name: Sau-yi Fong
Date and Time:

2016.9.15, Evening

Location: My apartment at 119th
Subject: Started growing

I spent a bit of time looking at different recipes for growing verdigris and decided to try Merrifield's (p. 118) which looked the most feasible. It says:

"If you wish to make the copper-green which is called Greek, take a new jar, or any other concave vase, and put into it the strongest or most acid vinegar, so as not to fill it, and put strips of very clean copper or brass over the vinegar, so that they may not touch the vinegar or each other, being suspended to a stick placed across the vase. Then cover the vase and seal it, and put it into a warm place, or in dung, or under ground, and leave it so for six months, and then open the vase and scrape and shake out what you find in it, and on the strips of metal, into a clean vase, and put it in the sun to dry."

It seemed to me that the key was to look for the right kind of vinegar. What kind of vinegar was the "strongest" or "most acid" in early modern context? I remember Professor Smith gave us a hint that we should use vinegar with "mother". I went to a grocery store near my apartment after class to see what options I had. I ended up choosing an organic apple cider vinegar that was labeled "Raw, Unfiltered and Unpasteurized, With the Mother". I don't know much about "western" vinegar as I grew up in Asia and tend to use rice vinegar all the time--but this one seems to fit the bill.

Following the instructions of the recipe, I poured the vinegar into the jar, but not too much because I wanted to make sure that the vinegar wouldn't touch the copper. Then I wondered how I should deal with the copper plate--should I cut it into strips or not? I don't think the old scissors I have at home are good enough for cutting the copper plate, so I decided to leave the copper in one piece. I folded the edge of the copper plate over the string so that the plate can hang on the string. Trying to make the copper plate suspended over the vinegar in the jar, I asked my roommate to hold the two ends of the string for me as I placed the string--with the copper plate hanging over it--across the mouth of the jar. And then I covered the jar with its lid, and "screwed down" the metal band of the jar so that the band pressed the string against the jar's rim. (I regret not taking photos about this process as I type it. It's really hard to describe this process in words!)



I put my jar on the window sill to make sure that it would receive enough warmth from the sun.

At first I was doubtful whether it would work, but the copper plate actually turned greenish the next day.

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Name: Sau-yi Fong
Date and Time:

2016.10.3, Morning

Location: Making and Knowing Lab
Subject: Painting out

Before going to the lab I took out the copper plate from the jar and put it into a Ziploc bag.



After putting on my protective equipment, I started working on my verdigris. I used a palette knife to scrape the verdigris off from the copper plate. The process was relatively smooth. The verdigris came off pretty easily in powder form. The color is gorgeous! I am so glad that it worked well.



And then I realized that the color of the verdigris from the two sides of the copper plate was a little bit different. One side produced a noticeably darker color. I'm still not sure why that happened. I think both sides of the copper plate had been exposed to the sun.



I divided my verdigris into two piles and started mixing the verdigris powder with oil. I tried walnut oil first, putting a drop of oil on the verdigris powder by using a pipette and mixing them with my palette knife. Then I realized that the mixture was a little bit dry, so I put in another drop of walnut oil.



Then I blended the mixture into a smoother form by using a muller. It's my first time using a muller and Professor Smith taught me to move my muller like writing "8" on the glass plate. The verdigris-oil mixture spread out on the plate and I put it back into a "pile" by using my palette knife. I think the verdigris turned more greenish after adding oil.
I repeated these procedures with linseed oil. For some reason I find the verdigris-oil mixture produced with linseed oil not as smooth as the one produced with walnut oil. It took me a bit longer to mix the verdigris powder well with linseed oil.



Finally I painted out the verdigris. The one on the right is made from walnut oil and the one on the left is made from linseed oil. The two colors turned out to be pretty much the same to my eyes, but both are such beautiful shade of green!

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Name: Sau-yi Fong
Date and Time:

2016.10.10, Afternoon

Location: Making and Knowing Lab

The colors did turn out to be different after a week! The one with walnut oil stays pretty much the same, whereas the one with linseed oil turns into a darker green.

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Name: Sau-yi Fong
Date and Time:

2016.10.17, Afternoon

Location: Making and Knowing Lab



After two weeks, the one with linseed oil is noticeably greener and a little bit more yellowish than the one with walnut oil. I think the one with walnut oil stays pretty much the same from day one.

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