Coils, Glazed & Finished: Fall 2022

coil spaghetti and meatballs by Yarelli Sanchez (the meatballs are hollow)

During the first and third project of the quarter in Hand-building, students were split into groups and they either worked with coils and slabs in the first 3 weeks or they worked with the 3D printer and extruder first, then switched later, to use those two techniques for the third project.

student work, coil form with sprayed copper red glaze in reduction

Coil building is the first hand-building technique I remember learning and the technique that I still use the most in my home studio, though in my own work I throw and pinch a lot and sometimes extrude, too. 

other side of the coil piece by anonymous

Coil building, along with pinching, feels to me like the fundamental clay building technique. I'm not sure if that is colored by personal preference or how I learned, but coil building as a technique is one that tends to be relatively easy to manage right away (without a lot of practice), meaning that relatively few students break or collapse their coil builds and have to restart. With slabs and the printer, it isn't particularly unusual to have to scrap the first attempt because the clay was too wet and heavy, or too dry. 

third view of the coil piece by anonymous

Over the years I have had students struggle with coils when they were trying a complex shape or when they were building that dramatic shape too quickly. I remember a student in the old building who kept trying to build an exceedingly wide bowl out of wet coils, but she didn't support the coils as they got wide and didn't let them dry once they started to sag. She wanted to build it all in one go without letting the clay stiffen up a bit before continuing. She may have been adding water to the coils which just made them heavier and more likely to collapse at that angle.

extra small coil piece by anonymous

Most students don't have such a difficult time getting started with coils, but I like to push them out of the comfortable zone. My coil project requirement is tht the work they create needs to be asymmetrical. Coils lend themselves to repetitive layers and subtle changes and the expected form is usually a round bulbous vase shape. But coils are versitile and can be used to create a wide range of forms.

Valeria Alvarez replicated another student's coil avocado from a previous quarter

By asking my students to build an asymmetrical form, they have to come up with an idea that is unexpected. I love this project because it allows so much freedom for the students, both allowing them to explore that freedom, but also forcing them to create something with that freedom (which is sometimes harder than working within tight constraints).

Thai See's crying coil sculpture (find her @Thaiidraws on Istagram) 

With this coil project, the students may choose to leave the coils visible or blend them to create a smooth or to create a base for an alternate surface texture or design. With visible coils, students must score and slip between each layer of coil. They must also take care to roll even, consistent coils, or make the visual decision to have the coils vary in thickness.

Duck with egg by Carlos Garcia Alcantar

With blended coils, the student can skip the scoring and slipping (I always do) and simply squish the wet clay together as they build. Blending coils like this is similar to making pinch pots, but you are constantly adding on more clay.

coil duck with egg by Carlos Garcia Alcantar

This quarter student approaches to this project were particularly diverse. Carlos started building his duck from about where the waist is currently. The legs were much different and the duck was sitting. Partway through the build, however, he decided to take off the old legs and base and start building new legs. 

This piece is entirely coil built and about 20" tall.

Building a standing form with just two legs is a bit risky because two small bases is less stable than three. I was worried, but Carlos made his duck/human feet large and he balanced the big arms and egg with a similarly impressive duck butt and tail. I was pretty surprised how well the duck stands on its own.

Carlos Garcia Alcantar, duck (behind)

Carlos attached the legs and feet to the body late in the process, but because of his careful planning and control of drying, everything attached well and the build was stable. Carlos kept his duck covered in plastic (and a warning not to touch) until critique, so he had kind of a grand reveal moment during that class.

Thai See, coil sculpture (side)

Thai was another student who rebuilt and revised her sculpture. In her case, she built the face first, and kept changing her mind about how she wanted the rest of the structure to be. In the end, she built a kind of body/shell for the face, with the unexpected additions of worm coming out the one side.

coil kracken by Brooke Mason

A couple of students, Brooke and Yarelli, treated coils as both building tools (the assignment) and independent parts of the sculpture. I worry sometimes when students decide to do this because it can be risky. In Brooke's case, the little coils that twist and turn everywhich way are less supported and strong than coils that are attached to one another. These coils can break during drying or when loading or handling before glazing.

side view of the "broken" spaghetti bowl by Yarelli Sanchez

In Yarelli's case, I was worried about both the thickness of the spaghetti piled inside the bowl and how well attached each of those coils is to it's neighbors. I was actually a bit surprised that the foot or the bottom of the bowl didn't explode during firing, but Yarelli explained how careful she was during building. 

Amanda Goodrich's shark eating a squid

Amanda's shark eating a squid sculpture came together with a surprise near the end. I saw her building on the shark body, but it seemed like I turned away for a moment, then suddenly there was a squid, already built, in the shark's mouth. 

Amanda's contrasting glaze is very helpful for distinguishing the shark from its snack

Now that I'm looking at them together (remember, students didn't all make the coil projects at the same time), I realize how many sea creatures we had this quarter. Thunder started us off with an abstracted blue and green octopus sculpture. In contrast to Amanda's squid and Brooke's kracken, the octopus sculpture focuses on the head and leaves out most of the legs.

I think Thunder was telling us about how the legs were short because it was a baby. Thunder used a mix of underglazes for his color, but, unfortunately the glaze didn't fully adhere to the underglaze and he had a couple of dry spots where it crawled away.

Octopus by Thunder Morales

Students mostly used glaze or underglaze plus glaze in the high fire kiln for their coil sculptures. Yarelli and Julia were the only exceptions. Yarelli used underglazes in a low firing for her spaghetti. She sprayed on her glazes and used tape as a resist to keep the overspray off of the broken part of the wall that had apparently fallen into the spaghetti.

Teapot by Carlos Garcia Alcantar

Brooke and Thunder also used underglazes, but in the high fire kiln. Anonymous used the sprayer to apply a high temperature glaze to their large sculpture and probably dipped the small vase. I believe everyone else painted on their high temperature glazes. I remember one day when the counter in the glazing room was surrounded by students with paintbrushes.

Coil form (after raku tragedy) by Julia Snow

Julia chose to put her coil form in the raku firing and use horse hair to decorate the piece. It actually survived the trip from the raku kiln to the shelf (via tongs) just fine, and I don't remember seeing any cracks on the piece during the critique. After critique, Julia left the work on the table. On the day of the thrower's critique, I started to worry that she wouldn't be back to move her stuff, so I moved it.

Coil form base, Julia Snow

Unfotunately for me, I lifted this piece by grabbing just one of the branch shapes. As I moved it to the cart, with someone else in my other hand, the bottom detatched itself from the part I was holding and the whole thing went crashing to the ground. Even worse, Julia walked in just a few minutes later to move her stuff.

The part I was holding when it broke

She took pictures of the work in its broken state. I'm not sure if she plans to repair it or not. The raku firing process can be stressful, and unfortuantely some cracks aren't visible (or didn't get noticed) until something else strains them. In this case, it was the weight of the sculpture itself, pulling against the crack.

3D Printed Pieces, Glazed and Finished: Fall 2022

 

Jordan Golob, Lego Minifig

The 3D printer is a relatively new tool in the clay studio, and one that I had never used before YVC purchased one. Because of the pandemic and my cancer year, as well as some time before the pandemic when it was down for repairs, we haven't really used the tool a great deal. (By my count, I think this quarter can only be the 5th or 6th quarter in which I required students to use it--but it may have been less based on how long it was broken.)

Brook Mason, printed sculpture

I starteed assigning the 3D printer as a tool for my Intro to Clay and Hand-building classes before I had properly learned to use it. When we started, the assignment was, essentially, here are the tools, here's what works, let's figure it out together.

Julia Snow, printed Tardis

I have a much better understanding of how the printer works now, and can help the students troubleshoot both the printer and software, as well as some basic troubleshooting in TinkerCAD, but there are still students who know TinkerCAD and 3D printers (the plastic kind) better than I do. What this means is that I regularly learn from students on this tool. 

Yarelli Sanchez, chicken pitcher

Students using the 3D clay printer this quarter had 2 main options for using the printer. First, they could used TinkerCAD or another program to design a 3D object and print it. The focus, if they choose this approach, is on learning TinkerCAD and planning for a form that the clay printer can handle.  

Amy Matson, Cats & Coyotes, printed and slab built 

The clay printer prints very soft, wet clay, which means that the clay sticks together fairly well when squished together, but it also means that it can't stand up without support.  If the printer squeezes out a line of clay on top of another line of clay, those two lines (coils) will stick and the bottom one will support the top one. The printer is very good at printing straight vertical walls of clay.

Carlos Garcia Alcantar, printed stacking forms

If the printer moves slightly to one side between levels, so that the top extruded line of clay is above but slightly to one side of the line below, the clay still sticks, still supports itself, but now the wall is at a slight diagonal. The printer can do this just fine and print cones, pyramids, vases, and similar forms. However, if the printer nozzle moves too far to one side between levels, the bottom layer of clay no longer supports the top layer and the top layer just falls into open space.

Carlos Garcia Alcantar, printed stacking forms

For this reason, the printer cannot handle overhangs, or flat tops, or the very top/middle of a dome shape. There are at least 4 ways to deal with these shapes. First, of course, students can avoid these shapes and design their print in a way that they aren't necessary. Second, they can print everything but the flat part or the top of the dome and simply add a slab or more clay later.

Derek Arneecher, printed shelves

Some students design their print in pieces so that only the verticals are printed and any and all horizontals are slabs added later. Jordan's Lego Minifig is a good example of this. She printed the body, neck, head, and cylinder on top of the head separately. She couldn't have printed the body and head, or even just the head in one piece because because the shoulders, the bottom of the head, and top of the head are all horizontals that would have fallen in. 

Yarelli Sanchez, chicken pitcher

Yarelli also printed her chicken pitcher in pieces, though in her case, some of them could have been printed together as one.  The transition from cylinder to cone on top could have printed as one, but she chose to print them separately. She cut off the top of the cone after printing, altered it, and used it as the beak. However, the three pieces of the handle and the feet had to be printed separately and attached later.

printed turtles, student work

All of the options I mentioned so far are for students printing a hollow form. The third and fourth options are to print with an interior support or to print an entirely solid print. In the student example above, the student, who wished to be anonymous here, designed the turtle in TinkerCad, but hte top of the back and head wouldn't print at this angle, so they adjusted the print settings in Simplify 3D (the software we use to "slice" our 3D objects into printable files. If you were to flip over any of these three turtles, you would find a latticework interior that adds stability to the horizontal or nearly horizontal clay walls.

Thai See (@Thaiidraws on Instagram), printed hand and hand-built snail

Thai printed her hand completely solid and carved away the excess clay later, after it had dried somewhat. This approach is more labor intensive in some ways, because it requires extra work after the print has been made, but it allows for less fussing with the software and may allow for a more complicated form that otherwise wouldn't print.

Amanda Goodrich, printed castle

The assignment paramenters for the printer allow for a completely different option as well. Students may print a simple form mulitiple times and simply use that form to create a more complicated form. Brooke's sculpture is a great example of this. She printed a pyramid 6 times, then attached each pyramid together in the middle to create a form that could never haver printed on its own. The end result is a sculptural form that would have been more difficult to make any other way. She went further by cutting and carving triangles into and through the printed forms after they were attached.

Brook Mason, printed sculpture

Derek and Carlos both printed simple forms that were meant to be displayed together. Derek's printed fomrs are a set of shelves, some of which are attached together. Carlos' pieces were designed to stack together to form a cube, but one broke before firing, leaving a gap in the design. 

 

Carlos Garcia Alcantar, printed stacking forms

Valeria's piece also broke before firing, through no fault of her own. It was a printed cylinder with printed shapes added to the surface after printing to create a more interetsting shaped vase. Amy did something similar, on a smaller scale, with her printed vase and tiny printed pyramid decoration on the surface.

Printed Vase, Amy Matson

Firings, Faults and Just Fun

 Raku Firing

broken biscuit in the raku kiln between firings

The most entertaining firing process we used in the YVC clay studio is the raku firing. Around the 1970s this firing process became popular in the United States. Theoretically the process derives from Japanese Raku, but when the process was brought to the US and UK, Western artists kept the part they liked and changed the rest. In Japan, Raku is a name for a process and ware done only by one particular family of artists. The work is removed from a hot wood fired kiln and doused in water. My understanding is that the glaze is black and the firing and cooling process causes cracking in the glaze. 

we had just removed the pots from the kiln and I liked the look of the red hot kiln interior

What we call raku is basically any firing process where the work is removed from a hot kiln and fire ensues. In they YVC studio, we have several glazes and slips that can be used for raku firings and we also have some horse hair (and sometimes feathers) that can be used for "horsehair raku".  In both cases, we fire the work in a propane fired outdoor top hat kiln. The work reaches a fairly low temperature of around 1800 degrees Fahrenheit (this is low compared to our glaze firing of around 2300 degrees F). 

Jazlyn Alexander three raku pieces

Once the glaze starts to melt, the propane is shut off and we lift up the top hat of the kiln (an insulated cylinder of expanded metal). In the old studiowe had a counterweight to lift the top hat, but in the new Palmer Martin building, we have a mechanical winch that lifts for us. 

students adding horsehair to their hot pots

We use tongs (and gloves) to remove the work for the kiln and either put it in a bucket of shredded paper and/or dry leaves or set it on a shelf for the horsehair process. In the bucket, the combustible material lights on fire and is absorbed into any unglazed areas of ceramic, turning them black or gray.

Horse Hair vases by Liliana Morales

For horsehair, students hold pieces of horse hair (or feathers, or sometimes human hair or leaves) on the hot, unglazed pot. The hot ceramic causes the horsehair to burn, crinkling up as it does so and the smoke is absorbed into the area of the ceramic closest to the fire.  Horsehair looks particularly nice, in my opinion, when the student has first burnished the pottery to make it smooth and slightly shiny, but most students just want to play with fire.

Yarelli Sanchez's extruded sculpture cracked and was partly dropped on its way out of the raku kiln

Both processes are risky, often resulting in breakage, especially when students insist on firing porcelain clay or large pieces. However, as someone who did mostly raku in undergrad and fired pieces larger than my students' work, I am hardly in a position to tell them not to risk it. I tell them the risks and we give it a try.

Derek Arneecher's Winifred after raku horse hair firing

This quarter, we did have some breakage. One student tried horsehair on maybe 5 mugs, all in porcelain, and all of which cracked as they were cooling. Yarelli's complicated extruded chain piece made it out of the kiln safely the first time (when Yarelli was not available), but our two-person tong work didn't hold up the second time and it slipped and cracked before she began to apply the horsehair.

Winifred after painting (he decided he didn't like the horse hair effect)

Derek's large Winifred portrait had a fine crack after the raku firing, which got worse when it was fired a third time. Derek didn't like the horsehair look, so he decided apply underglaze and low fire clear glaze and fire the work again. I think it was a good revision, but unfortunately the crack is more noticeable after the second firing.

Bisque Firing fun

I justed love this kiln load with Medusa and Charlie facing off

Loading a bisque firing in the studio is usually just a step in the process, but depending on the contents of the kiln, placement can be entertaining. This year I really enjoyed the kiln load that consisted of Valeria Alvarez's Medusa facing off with Amy Matson's Charlie from Heartstopper. During the firing, Medusa's gaze turned him to stone-ware (lol).

Derek's hexagonal printed forms fit into the decagonal bisque kiln in a pleasing way  

I also enjoyed loading Derek's hexagonal 3D printed forms in the bottom of another kiln load. We filled each one with mugs and small work from the throwing class (but I forgot to take a picture). I just like the look of the geometric forms inside another geometric form.

Bisque Firing Trouble

Though the bisque firings can generally be unexceptional and uneventful when all the work is well constructed and fully dry, in a shared studio with beginning students, some breakage is typical every quarter. The reasons are almost always the same and this quarter was no different. Handles, hands, or other features fall off because they weren't originally scored well, or because they dried unevenly.

Jordan Golob's 3D printed Lego minifig lost it's hands in the bisque firing

Work that was too thick or too wet may crack or explode during the firing. We try to avoid firing wet, thick, or obvoiusly damanged work, but it's sometimes difficult to know ahead of time. I'm also more lenient with handbuilders, who spend a lot of time on one piece than with throwers who make a lot of individual pieces in the same time. My studio employees tell me that I was more lenient (aka "too nice") this quarter and let more work go through the firing than I used to. Did I forget because of the long break, or did the cancer change me?

Jordan Golob's Dwight lost the back of its head during bisque firing

The other reason work can explode in the kiln is if there is a contained air pocket with no escape. We call this, as well as any too-thick work, a "kiln bomb" and I always tell students to pop a hole with a needle tool into any contained air pockets in a sculpture. This is easy, visually unobstrusive and always solves the problem. It is fascinating to me, then, that the idea of a contained air pocket blowing up in the kiln is controversial among potters and ceramic artists. 

Manuel Delgado's castle lost its roof during the bisque

Serioustly, if you'd like to start an online battle amongst clay folks, tell them that an air pocket will explode in the kiln. Immediately some of these folks will that you that it does not--and call you stupid in the mix. The argument, in essence, is that the air doesn't cause the contained air pocket to explode; it is the moisture in the air pocket. They will claim that any pieces that explode haven't been dried long enough. While it is true that sometimes air pockets don't blow up, they often do.

the castle with its roof back in place

As an undergrad, firing a load of sculpture in a raku clay body, I realized too late that my sculpture had no air hole and was surprised that it came out of the kiln just fine. I was told the groggy, low shrinkage clay body and thin walls allowed it to fire just fine. Since then my students and I, sometimes on purpose and sometimes by accident have tested it many, many times. Most of the time (but not always), the work explodes, while other work by the same builder, with the same clay, same thickness, and dried for the same amount of time does not.

An air pocket blew up Derek Arneecher's extruded sculpture during firing, and took a few other pieces out with it

This quarter we had two perfect natural experiments (though the student artists may not agree). I hope they don't mind me talking about their situations, because they are so instructive and the artists only had one tiny mistake that led to big trouble. Derek had made a large, impressive and well-constructed sculpture from extruded forms. His joints were scored and slipped well and reinforced. He let the work dry slowly and completely, then we loaded it in the kiln and fired the kiln slowly with a long candle (preheat to force out any remaining moisture from the clay). 

When it was time to unload the kiln, we discovered that his piece had exploded violently in the kiln, taking out some neighboring pieces as well. The only problem we could identify was that he had a hollow section in the middle with no hole--the walls of the form were consistent throughout, the whole piece had dried evenly, and the whole piece had been inside the kiln for the same long candle. The legs and top were intact and the explosion, though violent, clearly was focused in that middle hollow section.

Derek's extruded robot after repairs

That day, during critique, I kept reminding students to pop a hole in their sculptures so that what happened to Derek wouldn't happen to them. Another student, Manuel, explained, during critique, that he had not popped a hole in the towers of his castle, but that he would do so before they were fired. Though he did pop a hole in both towers, he forgot that there was a separate contained air pocket inside the roof, which was separated from the top of the tower. Though his work was also fully dry and in a kiln with a long candle, the roof blew off during firing, again illustrating that hollow pockets explode. 

Derek's scupture after painting

The very next day, I read a long post by a well-known ceramic artist on Istagram listing myths about ceramics. One of his myths, and one that got a lot of attention by commentors, was that contained air pockets don't explode during firing. I'm not sure if the argument is semantic (i.e. the air doesn't expand; it's the moisture in the air expanding), but I find it kind of mind-blowing that people will insist that something that happens regularly does not, in fact happen. 

Low Firing & Underglazes

low fire glaze kiln, first load

In the clay studio, we regularly have 5-7 distinct firing types. We have the bisque firing, which is the first firing that turns the clay into ceramic and makes it stronger and easier for students to glaze. Hand-builders are also allowed to paint their work at this stage if they like. Most students glaze their work to cone ten in either an oxidation or reduction atmosphere. Students may choose to raku fire their work or do a pit or smoke firing (which no one requested this year). Intermediate students have the opportunity to use overlglaze lusters or decals, and hand-builders may low fire their work, using underglaze and a low fire clear glaze.

Oops, underglaze, which doesn't flux (melt) in a low firing can flux enough to stick to the biscuit in the high fire kiln

Underglazes are basically commercial colored slips, meaning they are made of clay, water, and color. The color in underglazes has been produced commercially so that it is fairly stable and looks pretty similar in the jar, on the freshly covered clay or ceramic object, and in the firing. Homemade slips may have color, but that color may change in the firing.

carved and underglaze decorated bowl by Liliana Morales

Underglazes are designed to be fired to a low temperature, meaning that those bright colors look best at that low temperature and in a neutral atmosphere, the kind we have an an electric kiln fired just a tiny bit hotter than our bisque kiln. Underglazes can be great. I use them extensively in my own work because they are bright, easy to use, and because I can layer them in my sculpture. Students like them because of the bright colors and because they stay put and don't run in the kiln like some glazes do.

sgraffito vases by Liliana Morales

Underglazes can also be fired to higher temperatures, which we do in our studio, but not all the colors can handle the higher temperatures (or the reduction atmosphere). Though I try to be clear with students about the risks, students are sometimes surprised that their underglaze colors disappear at the higher temperatures. Additionally, because underglaze colors can melt at the higher temperatures, some undergalzes can stick to the shelf or kiln wash in the high temperature kilns (something they do not do at low temperatures because they are not glazes).

High Fire Surprises

The interior of Yarelli's printed chicken pitcher had far too much glaze

The main glaze temperature for our YVC studio is cone 10, around 2350 degrees Fahrenheit (I always say around because clay and glaze firings are measured in cones that measure the heat work of tempeature and time. If we fire faster, we might reach a higher temperature than if we fire slower, but both are cone 10.) 

Searra Rodriguez, pitcher, Something went wrong with this particular Shino in the oxidation firing this quarter

Our main studio clay bodies are designed to "mature" or "vitrify" at cone 10. That means the ceramic is no longer porous at that temperature. What this means is that we fire functional work to cone 10 so that it will hold water and be strong. The mature ceramic can be washed in the dishwasher, microwaved, and put in the oven. The glaze is there to make it look pretty and easy to clean. 

oops, this spoon jumped off its stilt and onto the baffle brick during the firing (yes, we need a new baffle brick) 

Low fired ceramic with glaze, while also looking pretty and being easy to clean, is not vitrified and thus can absorb water. This makes it less than ideal for functional use. Immature glazed ceramics can get very hot in the microwave and can get downright stinky in the dishwasher. It is also more fragile. In our studio, besdies raku, which is mostly just for fun, functional work needs to be fired to cone ten, while the low firings are reserved for sculpture and purely decorative items.

Functional pottery and Carlos Garcia Alcantar's extruded hand, before firing

We have two types of cone 10 glaze firings in our YVC studio.  Kiln amosphere refers to how much oxygen is available in the kiln compared to fuel or fire. In a gas fired kiln, we can control how much fuel and how much air enter the kiln. When the mix is even the firing is efficient and the kiln heats up fairly quickly. If we artificially reduce how much air is available in the kiln, the fuel will pull oxygen from materials in the ceramic and the glaze.

Yarelli Sanchez's dog, Carlos' hand, and other work after firing

Both the clay and the glazes can look different in a reduction versus oxidation or neutral atmosphere firing. We usually start the quarter with reduction, then fire at least one or two more firings of each. In our studio, the stoneware clay gets brownish and a bit speckly in the reduction kiln. We have a copper glaze that turns oxblood red in reduction an another glaze that turns purple in reduction.

Carmen Nelson teapot (detail)

The copper red turns a transparent green/turqoise in the oxidation atmosphere, while the purple looks light blue in oxidation. In Carmen Nelson's teapot above, it appears that the thin application of the copper glaze in the reduction kiln didn't allow it to turn red except where it was thicker or where it interactive with another glaze (to increase the thickness). The sometimes surprising or unexpected ways in which the glazes interact and react in the kiln can be one of the most rewarding and most frustrating parts of the ceramic firing process.

Overglaze Enamels and Decals

I don't always have intermediate students in my class, but when I do, I like to offer them the opportunity to try some overglaze decoration options. Overglaze is a low fire process (or processes) where a decal is applied or an overglaze is painted onto the surface of a piece that has already been fired to a higher temperature. The decorated piece is then fired to a much lower temperature that makes the decal permanent or changes the overglaze.

Jazlyn Alexander, decals

In our studio this quarter, I had some colored decals, as well as mother of pearl and gold luster enamel overglaze. My intermediate student, Jazlyn used some of each. Another student, Liliana, provided her own lusters and we fired quite a lot of work with the gold luster.

Liliana Morales, gold luster vase set

The gold luster doesn't look like much before firing. Because of the cost, the jars it comes in are laughably tiny, and the luster does not look gold when it goes on. The firing changes it so that it comes out of the kiln metallic and shiny. It is highly noticeable in person, where the light can reflect off of the luster and draw one's attention to the work.

Jazlyn Alexander, mushroom with gold

Gold luster is usually used minimally on functional or decorative work, both because of the cost and because the low temperature makes the overglaze a bit less stable for functional pottery. Commercial work with overglazes often recommends hand-washing and avoiding the microwave. I've used the dishwasher for pieces with gold luster decals and they seem fine, but I'm more lazy than careful about using my own work.

Jazlyn Alexander set with mother of pearl

The mother of pearl overlgaze is very subtle and has to catch the light just right to even be seen. In the set above, Jazlyn's plate has a bit of mother of pearl on the top edge, but I cannot see the mother of pearl in the indents of the mugs (though I believe it was visible in person).