A Question all Newbies to enamel art ask?
Most books on the subject of enameling are pretty general on the scientific makeup of vitreous enamels: A blend of flint, sand, potash, soda, lead and metal oxides. Nothing further, no bells or whistles, no mention of secret formulas.
When I was a student of enameling, I didn't think too much about those tiny little grains of glass, except how they melted. But over the years I have listened to countless exchanges between artists on which enamel manufacturers produced the best enamels. Everyone had their favorite from different countries of origin, but not one person offered any scientific fact of what makes their particular brand so special over the rest. Like the old saying "all salts are the same", I wondered if the same held true for enamels. I decided that in order to write this article, I needed to ask the experts.
I contacted Coral Shaffer of Enamelwork Supply, Jim Flood, Bovano of Cheshire and Tom Ellis of Thompson Enamel. They in turn gave me their take on the subject then pointed to "The Source", Mr. Woodrow W. Carpenter, owner and manufacturer of Thompson Enamels for over 70 years.
This is Mr. Thompson's response on the topic of "SALT":
"Much depends on our backgrounds. For a chemist all salts are not the same. Chemically, a salt is formed when the hydrogen of an acid is partly or wholly replaced by a metal. Sodium Chloride (NaC1) is the one every one knows. But there are many."
... and Mr. Thompson on the topic of "ENAMELS":
"Enamel is not a stoichiometric material similar to water (H2 0). If another oxygen (0) is added, hydrogen peroxide (H2 O2) is formed - an entirely different product. With enamel, adding or reducing oxygen produces another enamel. Any of the elements can be varied, each time producing a different enamel. In other words, the number of enamels possible is infinite. However, the area of usable enamels are somewhat limited."
Now for the answers to my "QUESTIONS":
Ques. #1: Does each manufacturer make their own formulas?
Ans: Yes, and they do not vary much.
Ques. #2: Is the quality of color based on secret oxide formulas that each company invents?
Ans: Yes
Ques. #3: Is the quality of the enamels based on each company's different manufacturing process?
Ans: Very little
Ques. #4: Is the enamel formula used today, the same as centuries ago?
Ans: Enamel formulas used today are much different than centuries ago.
Ques. #5: Other then leaving out the lead, does unleaded enamel have the same properties as the leaded enamel?
Ans: We have thousands of cutomers who find no difference.
Ques. #6: Do the chemical properties of flint, sand, potash and soda vary from country to country and can that be one reason why the manufacturing of enamels around the world is different?
Ans: We find little, if any difference. In fact, many of our chemicals are imported.
I also emailed Mr. Frank Dufour of Soyer Enamels on the subject, but did not hear back. But I did watch an informative video on how enamels are produced (without the secret formulas) . website: www.emaux-soyer.com
In conclusion, I now have a drawer full of exotic salts and a global inventory of vitreous enamels.
