Pearl on Jewelry

I love pearls and use them quite often in my projects. Normally, glueing pearls onto the piece would be the very last step in these projects. Selecting good quality epoxy and careful work in glueing were everything I’d care about until I started the project I am working on now. My client brought me in an old pearl brooch to be made over as something else. It was made in 14K gold with cultured sea pearls. This time, an initial move that I needed to make in executing this project was to remove the pearls from the piece.

The fastest and easiest way to do the task would be purchasing a chemical solution that dissolves the cured epoxy, which I was already aware of. But, it’d never hurt to research more if there is any better resolutions to do the job. Google had led me to stumble upon numbers of articles regarding the subject which could be narrowed down suggesting two methods.

First, use indirect heat to detach the pearl. Pearl is extremely susceptible to heat so that we all know we may never apply direct heat on pearl, such as torch, heat gun, etc. So, most articles recommended either using microwave oven or boiling in a pot until the pearl gets loose. The tricky part is how do we know when it’s the right time to fish out the jewelry in the boiling pot or microwave dish with water, and check the pearl is loose. What if we overheat the pearl and damage it? Especially, using microwave oven didn’t convince me getting the job done at all knowing microwaves change molecules. They may affect the molecules in pearl and result in damaging it.

The next option was a well-known method using dissolvent. Acetone is one of the dissolvents to free the pearl attached on jewelry. The only setback of this trick is that acetone may take away luster on pearl’s surface. So, after spending a couple of hours conducting research, I drew a conclusion that I should go ahead and place order ‘Attack’ from Rio Grande.

‘Attack’ is an adhesive remover which is mainly Dichloromethane. It dissolves cured epoxy as well as polyester resins. The same chemical is widely found in paint stripper products and also used in food industry to decaffeinate coffee and tea. As ‘Attack’ is classified as a hazardous material, it had to be shipped separately from other items and only ground shipping. The container is too much secured in my opinion which I had a hard time just opening the lid. (Maybe it was just mine) The solution was clear and turned purple as the glue was dissolved in. It took me about 12-14 hours to successfully detach the pearls on the brooch. I think it’s because whoever did the job applied too much glue on the pearls. Another piece I tried took me less than 12 hours to complete the task. So, I would say the pearls’d be free after submerged in the solution about 12 hours.

The detached pearls kind of felt sticky, so I gently and quickly rinsed them in acetone and then warm water with soap. They are ready to fulfill a new purpose.

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Argentium Experience

Recently, I completed a project for my client using argentium. This was my first time experience with the fairly new metal. Although it’s considered as sterling and I have been working in sterling silver for years, I thought it’d be safe to do a little research before actually working on the metal. There were enough published written materials as well as helpful videos that spare me the knowledge. Above all, argentium is widely known as non-tarnished or tarnish-resistant sterling silver which doesn’t form firescale. This is absolutely beneficial knowing no need to protect the metal surface when soldering. Flux causes much of a hassle when soldering (You’d know what I’m talking about) and clean-up process between soldering takes so much time.

These are a few things what I learned from my experience.

# Argentium is quite easy to saw and file. I used a 20-gauge sheet to make a back plate and a 16-gauge square wire to make a thick rectangular bezel. The metal felt like butter as I saw off and file the excess. It was dense but easy to file as if I was filing aluminum without any residues being caught in the file.

# Argentium doesn’t conduct heat as much as traditional sterling. This means I was able to localize the torch at the area I want to melt the solder. It was more like soldering gold than silver since I didn’t have to heat up the entire piece.

# However, melting temperature of argentium is about 60 degree lower than that of traditional sterling. So, in general, medium solder is recommended as to hard for traditional sterling. As I didn’t order solder specifically made for argentium, I used medium silver solder that had in my studio. Some materials advise to use the solder for argentium because of the color match, but I haven’t found any color difference in the soldered seam using the silver solder.

# I found extremely convenient soldering argentium without flux. Since no flux is involved, no fluctuating solder pallions as I heat up the piece. Just flux the joint and liquid type works fine. Handy flux is not recommended for argentium. However, be careful with selecting the torch tip as argentium holds heat well, which means you have a good chance of overheating the metal. I used #0 torch to solder every part of the pendant. As soon as I saw the piece turns into red, I took the torch away.

# Annealed argentium is extremely malleable that can be easily formed into other shapes and forms. However, when it’s red-hot, it’s also very fragile and could be broken. After annealing a beveled 16-gauge square wire, it broke in two pieces as I grabbed with tweezers to submerge in water. So, let it cool for a while. This is very important if you don’t want to break your piece.

# Finally, although argentium is highly tarnish-resistant, prolonged soldering may form cupric oxide on the surface. This can be removed in a pickle pot or by sanding the surface. I used 600 grit to lightly sand off the cupric oxide.

# The most impressive thing about argentium is perhaps the efficiency. It saved me a lot of time. I know what it takes to solder traditional sterling. Keep the metal from being in contact with oxygen ALL THE TIME. Argentium requires far less work to keep metal clean and almost no clean-up. It was truly a fascinating experience.

Bronze Stirrups from the Unified Shilla Period

When I came to the United States in 2006 and started learning about American culture and people, I noticed that many Americans are interested in antiques. I grew up in a traditional Korean architectural home until I was seven, and antiques were frequently encountered when I visited my grandparents’ house. They had old furniture, ceramics, utensils, tableware, books, etc, but I don’t remember hearing anything about honoring antiques. In fact, the state government in Korean history initially appeared in the 7th century BC in the Chinese record, and we have tons of artifacts left from the Paleolithic period. Starting from the late 1960s’, Korea was under development, and everything was getting modernized at a fast pace. I assumed we did not appreciate properly what was left behind through the time. I kind of felt ironic, and that motivated me to revisit my cultral heritage.

stirrups 1

Since ancient Koreans used bronze to cast weapons, tools, jewelry and everyday objects, it had been their favorite material until iron started substituting bronze around the 4th centurty BC. Iron was more appealing in terms of the durability and light weight. Imagine cavalry heavily armed with bronze weapons and armours, and the horse protected with a bronze helmet and saddle. Unified Silla spans from the late 7th century to the early 10th century, and this is the only pair made in bronze in this era to be passed down to present. In this sense, the pair of bronze stirrups from the Unified Silla period is a rare artifact.

stirrups 2

What makes this artifact unique is, in my opinion, originally finished with laquer on the surface. Laquer finish on bronze cast object was invented by the ancient Chinese to prevent corrosion on bronze tableware from getting in touch with food. However, the laquer paint on the stirrups served a different purpose: enhancing the durability of the material. Later, in China, Korea and Japan, laquer surface treatment is often used on wood objects to keep the material from decomposition as well as to provide rich colors.

stirrups 3

In addition, unlike any other stirrups observed in these days, the form of the artifact mimics those of shoe which I find interesting. It seems as if the artisan had put aesthetic on the same level with the function of the object. As it is shown in the close shot, the surface is decorated with patterns of flower and flame. They are elaborate and meaningful in Korean culture.

stirrups 4

Bronze Stirrups from the Unified Silla Period (8~9C)
Bronze, lacquer, cast.
14.7cm x 12.1cm x 14.9cm
Photos: Gyeongju National Museum

This is how it begins…

Honestly, when I graduated college many years ago, I didn’t think I’d go back to school later in life and wind up doing metalsmithing and making jewelry. As a history major, I had several friends who were interested in art history, and one of them pursued graduate studies in the ancient Korean art. I still remember her saying how ancient artifacts, they were mostly created in metal, made her feel wonderful just by looking at them.

According to scholars, ancient Koreans knew how to cast bronze into weapons as early as the 10th century BC. I was blessed enough to grow up in a culture where metalwork was accessible in everyday life. My family owned brass bowls and silver utensils with enameled decoration until they were replaced with stainless steel material for convenience. As a custom, a new-born baby on her/his first birthday receives pure gold rings with prints individually weighed about 0.12 troy ounce from relatives and family friends. Field trip to a museum full of the ancient metal artifacts was a yearly routine for kids while in school.

Looking back, as I am now working in metal, I realize how great the influence was.  I desire to know where my metalsmithing DNA originates from.