Good News & Bad News

From Troy McFarland: Art From Scratch

I've been reading The Materials & Techniques of Medieval Painting By Daniel V. Thompson on the bus for a couple of weeks now.

I'm pleasantly surprised that some of the techniques I came up with to create a pigment are listed in here. For example, I took a patina recipe on the web (salt, ammonia, & vinegar), and experimented with it until I found that using just vinegar produces the best pigment. This was done a variety of ways in Medieval times for the same reason. The pigment is called 'Verdigris', also described in the book as an 'acetate of copper'.

That's the good news.

The bad news is that I just did an MSDS search on the effects of Copper (II) acetate, and it is not safe at all. Here's the MSDS, and here is the wiki entry on it.

By the way, vinegar fumes will create lead white pigment, which is potentially even scarier than copper (but not by much, it would seem)

I may continue to use this green pigment, but maybe it would be safer to stick with ground malchite.

Hazards listed on the MSDS site (thankfully I've been using a resperator & keeping Ravenna out of the garage with working with it):

Emergency Overview
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DANGER! CAUSES EYE BURNS. HARMFUL IF SWALLOWED. CAUSES IRRITATION TO SKIN AND RESPIRATORY TRACT.

SAF-T-DATA^(tm) Ratings (Provided here for your convenience)
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Health Rating: 2 - Moderate (Life)
Flammability Rating: 1 - Slight
Reactivity Rating: 1 - Slight
Contact Rating: 3 - Severe
Lab Protective Equip: GOGGLES & SHIELD; LAB COAT & APRON; VENT HOOD; PROPER GLOVES; CLASS D EXTINGUISHER
Storage Color Code: Green (General Storage)
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Potential Health Effects
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Inhalation:
Causes irritation to respiratory tract, symptoms may include coughing, sore throat, and shortness of breath. May result in ulceration and perforation of respiratory tract. When heated, this compound may give off copper fume, which can cause symptoms similar to the common cold, including chills and stuffiness of the head.
Ingestion:
May cause burning pain in the mouth, esophagus, and stomach. Hemorrhagic gastritis, nausea, vomiting, abdominal pain, metallic taste, and diarrhea may occur. If vomiting does not occur immediately systemic copper poisoning may occur. Symptoms may include capillary damage, headache, cold sweat, weak pulse, kidney and liver damage, central nervous excitation followed by depression, jaundice, convulsions, blood effects, paralysis and coma. Death may occur from shock or renal failure.
Skin Contact:
May cause irritation with redness and pain.
Eye Contact:
Corrosive. May cause irritation, redness, pain, blurred vision, discoloration, and damage.
Chronic Exposure:
Prolonged or repeated skin exposure may cause dermatitis. Prolonged or repeated exposure to dusts of copper salts may cause discoloration of the skin or hair, blood and liver damage, ulceration and perforation of the nasal septum, runny nose, metallic taste, and atrophic changes and irritation of the mucous membranes.
Aggravation of Pre-existing Conditions:
Persons with pre-existing skin disorders, impaired liver, kidney, or pulmonary function, glucose 6-phosphate-dehydrogenase deficiency, or pre-existing Wilson's disease may be more susceptible to the effects of this material.

Vinegar + Copper = different types of Green!

I haven't added to this blog for waaay too long! The reason? I was laid off in late October, and was looking for a job for a little while. It was hard to justify playing with copper, bamboo, and crushed egg shells when I had to pay the bills. But, I found one (really looking forward to this new company!) and will be moving back to the states in a FEW FREAKING DAYS. I'm looking forward to being moved in, but I'm going to miss my Canadian friends, cheap golf & poutine.

I'm in the moving eye of the hurricane right now, with nearly everything in boxes, including the project. I have one new update: A vinegar/copper test matrix! So, if you've been following the entries, you'll see that I took a patina recipe online, and kept testing it to see what ingredients were actually needed. The original recipe was ammonia, salt & white vinegar. I found that anything with salt made the pigment too clumpy when mixed with walnut oil. Ammonia didn't really help much, and I think I read somewhere that Ammonia + copper = some type of carcinogenic substance (I'm probably wrong; I have NO chemistry background, and I was tired). It turned out that just white vinegar & copper made some really nice blue-green crystals, which mixed really well with walnut oil. (A horrible patina, but a great pigment).

Since white vinegar is not going to be as easy to make as apple vinegar, I decided to try a range of vinegars to see what I could get. I also tried balsamic vinegrette, but it just turned to muck.

The results: four different shades of green! I re-did the white vinegar, and the results are very similar (I have a comparison shot, but am too tired/is not enough room/am saving it for the coffee table book).





I'm guessing the impurities are causing the color changes. No matter, they all look great! (you'll notice on the red wine vinegar, I didn't scrape part of it off, that was because that was where most of the impurities settled)

Back to packing: I decided to clean the patinas that I tested before packing them up. There is an interesting orange/red under the thick green patina layer. I picked it up with some paper towels. I don't know if there is enough color to make a production run, but I just might continue experimenting with this in the months to follow.

Enter the (Copper) Matrix

I thought I had some really promising results with the copper tests I did using the salt, white vinegar & ammonia recipe, so I decided to do a test matrix to see what would work best. (No, it did not include Trinity as played by Carrie-Anne Moss but next time you're in your home town, feel free to drop by and say hi to me & the family), I just tried every ingredient combination.



I got a whole bunch of interesting results. Long story short: Salt seemed to make it hard to disperse in walnut oil (it was all clumpy)






My best result is to only use white vinegar. I also thought I had an incredible blue with an ammonia/white vinegar combo, but after I mixed it with walnut oil, it reacted and turned green.







One other thing, as noted on some of the close-ups, I had reactions between the tests. My guess was that the vinegar & ammonia vapors reacted in the air just above the copper & oxidized it.



So, one more thing to try with copper before moving on: I need to do a few more tests with different types of vinegar. This time I’ll keep the samples a little further apart.

Copper, Now with Ammonia!

After finally getting a hold of a bottle of Ammonia, I was able to try out the original, unaltered patina recipe. Here’s the recipe (courtesy the Urban Farmer Store) and my results:

2 cups White Vinegar
1 ½ cups Ammonia
½ cup kosher or sea salt (according to the recipe, more salt = more green, less salt = less green)

By the way, the vinegar and ammonia each had a powerful smell, but once this was all mixed together, the smell was not bad at all.

Day One: Cleaned and scoured out the copper post-topper, then filled with clear liquid.



That evening, the solution had turned a wonderful blue hue.



About 4 days later, here are the results, with still a little liquid at the bottom. As I put less salt into this batch, there are a lot less crystals.



Eight days after making the batch and it is dry. Note how the color at the bottom is more blue than the rest. This may be due to it getting rained on outside last night (I left it outside to dry out a little faster and forgot to bring it in).



I did a little research on how to make vinegar and ammonia from scratch.

Vinegar won’t be hard… I have a friend who has made a few bottles accidentally when home brewing. Ammonia will be a bit harder. Today it’s made using the Haber Process, which uses high pressure (200 atmospheres) and high temperatures (450 C) and an iron catalyst to get Nitrogen & Hydrogen to react and form Ammonia. There are some other historical ways to produce it, and I may try those (playing vegetable and animal waste products… joy.). My other substitute (see last entry) seemed to do a pretty good job, but it began to smell pretty bad towards the end of the experiment.

So, I’m going to do a matrix test of the four ingredients (salt, vinegar, ammonia, and ammonia substitute) to see if I can eliminate any one of them. Here’s my two test sheets:

Go Green!

Right now I’m facing a catch-22 regarding my first production batch of pigment. I need to make some pots in which to refine my pigment more, but in order to do that I need a kiln. Although I have some clay to make bricks or pots, I don’t have anything to fire them in…

That and I don’t think my landlord would really appreciate me making a bonfire on his property to pull this off. This sort of thing needs done at my parent’s property.

So, in the meantime, I’m trying to expand my color palate. I’m about 1/3 of the way through tests for creating a copper green pigment. Here’s what I’ve got so far:

I found a recipe for patina on the web, which consisted of only three ingredients: Sea/kosher salt, White Vinegar, and Ammonia. We had the salt and vinegar at home. Believe it or not, finding a cheap $3 bottle of Ammonia was *not* easy. I called or looked in over five stores before I found it in stock at Safeway. Why so scarce? My guess is that it’s a cheap ingredient used in the manufacture of meth, so people are either buying up all the stock, or stores are not selling it to attempt in vain to cut down on meth production. Come on everybody! Haven’t people figured out yet that speed kills? Now it delays art projects too.

So, while I was looking for ammonia, I tried a substitution for my first batch… one that would be easier to make from scratch too. Let’s just say that it’s a) it complies with my ‘from scratch’ rule set b) a liquid and c) I can currently manufacture more in a week than I’ll probably need for this entire project.

I also tried just using lemon juice for a second test, but it just resulted in making a green snot-like goo. When I added alcohol to it, it looked pretty bad.

Both batches on day 2 or so



Day 3 or so: Crystals began to form



Close up of crystals



Day 5, Had been left outside for a while, including a light mist of rain.



Icky green goo from dehydrated lemon juice. I couldn’t tell if the green color is from the copper or some nasty bacteria. So, I mixed it with alcohol to see if I could sterilize it and separate the pigment out.



Final bottled samples. Middle sample has settled since this photo and all pigment and salt is at the bottom.