Friday, October 29, 2010

Fireborn Studios: Profile of Dan Vito and Donna Hetrick

Fireborn Studios

Located at the corner of 24th and Sarah Streets, Pittsburgh, PA 15203 

Dan Vito

Donna Hetrick

Dan and Donna have been making and selling pottery for over 30 years, and over that time their work and how they have marketed it has evolved with the times.  Currently Donna is teaching art in the Pittsburgh Public Schools, and Dan is teaching classes at their studio and running the gallery where their work is exclusively sold.

In the past they sold through craft fairs, numerous galleries, wholesale outlets, and their retail shop.  Public school art teaching was also a large part of the equation for a while, with Donna currently teaching and Dan having taught for 15 years.

Since I have only interviewed Dan, much of this profile reflects his perspective but I hope to talk to Donna soon to include her input.

I have to say that they maintain one of the better websites that I have seen potters put up.  If you are a potter, you would be well served to go through it to learn effective ways to connect with the public.

Also, my tour through their studio contains reflections of their evolving efforts to market their work.  Donna's teaching job enables Dan to focus on doing more creative work and on his students who take classes in their studio.

The Gallery

The front of their studio contains the gallery.  The stock the gallery with their own pottery and with other artist's handmade glass and jewelry.

The best way to view the gallery online is the following link:

The Classes.

Since students take classes in a working studio, Dan has laid out specific instructions to establish guidelines that enable students to work and receive instruction while minimizing the disruption to a working studio.  The website provides extensive information to make expectations clear to prospective students:

Current students are also provided with a set of expectations and resources to insure a workable relationship for both.  This information is too extensive for inclusion here, so I urge you to click on the link below and check it out yourself.

Among other things, students enjoy small classes, use of the porcelain clay and glazes that Dan and Donna use for their own work, frequent firings, and individualized instruction.  

Student's pottery from recent firing.

Fireborn has a bisque firing room with electric kilns and ventilation.

Bisque storage.

Teapots in progress.

Glaze room.  Students have a choice of 35 glazes.

Adjoining the glaze area is a 100 cu ft gas kiln that is fired to Cone 11.

In the past to support their wholesale pipeline, Fireborn utilized a jigger for bowls and other forms.

Jigger in use.  Dan preferred to hand trim the bowls to achieve the aesthetic look he desired.

Fireborn also maintained a casting station to supplement their throwing and jiggering operations.

 Their backyard contains a small kiln and glaze spraying area in addition to an assortment of plants and flowers.

There is much more to show but I have to stop somewhere.  Visit Fireborn's website to see more, including a professionally made video.  All in all, very impressive.  Below are three pieces that are representative of their work.
Bottle with Shino glaze.

Shino platter.

 Tea set.

Additional pictures are available only at the following links:

Wednesday, October 27, 2010

Profile: Jeff Schwarz

Jeff Schwarz: A profile.
Ceramic Artist 

 Jeff in studio with friends.

Jeff's grew up in the area and began his ceramics education with a BFA from Slippery Rock University with Dick Wukich.  

After a year that included marriage to wife Judy, a designer, and supporting himself from his work, he received a 3 year fellowship to Syracuse University.  He then earned an MFA at Syracuse with such teachers as David MacDonald, Errol Willett, and Margie Hughto.  Jeff gives a lot of credit to his teachers in his development as a ceramic artist.  He also spent almost 10 years as a studio assistant with Ed Eberle, which he said was of great benefit to him.

After the MFA, the Schwarz's were considering a move to either Switzerland or Philadelphia.  However, they were offered a house in Pittsburgh from Judy's family with the understanding that they would do extensive repairs.  Currently, Jeff's studio is the basement, a cramped space which he has made work well for himself.  He is also building a wood fired kiln on property in Portersville, PA and will document for the blog.

Studio with wheel

  More studio.

 Standard Ceramic slab roller (he likes it a lot).

Kiln Room.

Jeff has been very involved with community and currently is the unpaid director of the ceramics program at Braddock Carnegie Library.  

He also is very involved in the Ceramic Water Filter project which was profiled on our blog.

Jeff is also an Adjunct Professor of Art at Community College of Allegheny County.

Along the way, Jeff also worked at Manchester Craftsmans Guild.  The Guild served as the host institution for the 2008 NCECA conference and Pittsburgh was a late substitute for the New Orleans site due to the devastation there.  

Jeff worked with Josh Green and many others to pull together a great conference and helped to show off the Pittsburgh area's gallerys, schools, culture, and ceramic artists. Some links to the event can be found here:

To see Jeff's work up close and personal you should go to the Christine Frechard Gallery at 5871 Forbes Avenue, Pittsburgh from November 6 - December 10, 2010.  Jane Haskell's work will also be shown.  

Pictures of some of Jeff's recent work follows:

Blood of My Father

Urban Rural Pink


I Know

Masked King

Blue King

Mnemonic Trigger



Pink Masked



Urban Rural Blue

Coming and Going


Too Much

Wednesday, October 20, 2010

CRAFTED: A Collector's Series - Mugs

If you're a collector of mugs or wanting to start a collection, you have the chance at the Society for Contemporary Crafts in their first of a series of Crafted Events.

For the first Crafted event, they have chosen to spotlight ceramic mugs—functional and affordable, these objects are a great way to introduce the idea of collecting. This is an excellent opportunity to add to your ceramic collection, or to begin collecting!

Reservations for Crafted are $20, and this cost will applied to the price of your mug. Mug selection will be on a first come, first served basis, beginning the evening of the event. Enjoy hot specialty drinks such as Irish coffee and Spiced Cider, hors d’oeuvres, and live entertainment with the purchase of a mug. Pennsylvania artist Daniel Kuhn will be demonstrating raku firing outside and Missouri artist Bo Bedilion will give a toast about the joy of collecting and using handmade mugs.

Thursday, October 21 · 5:30pm - 8:00pm
Society for Contemporary Crafts
2100Smallman Street, Strip District
Pittsburgh, PA 15222

There are a limited number of mugs available, so reservations are strongly encouraged. To make reservations, visit our website:

Monday, October 11, 2010

The New World of Crystalline Glazes: Developing Beautiful Crystals in Reduction

The New World of Crystalline Glazes: Developing Beautiful Crystals in Reduction
by Diane Creber
Ceramics Monthly, October 6, 2010

piece by John Tilton

Crystalline glazes are seductive and instantly capture the eye. How exhilarating to create a glaze that suggests floating galaxies, frosty windows, rare gemstones, or flowers. Enthusiasm for this glaze technique has greatly increased over the last few years, perhaps because of new advances in kiln technology and computer temperature controllers. Many more potters are now exploring the potential of this glaze technique, making new and exciting discoveries, including reduction firing (see “Reduction Firing Crystalline Glazes” below).

However, before exploring the possibilities of crystalline glazes, the potter needs to understand the basics. The process of creating a crystalline glaze is more involved than working with a regular glaze as it has a tendency to run off the pot and the firing cycle is very dependent on accurate temperature measurements.

For the purpose of growing crystals, the kiln is taken up in temperature to around 300°F beyond the melting temperature of the glaze, (typically cone 6 to 12), which allows some of the zinc-silicate nuclei, or seed crystals, to dissolve. The crystals will grow from the few remaining nuclei.

After reaching top temperature, the kiln is cooled either by shutting it off or using a predetermined cooling rate, until it reaches the temperature where the crystals will grow. This is usually somewhere around 2100°F–1900°F. 

When the glaze is molten, all these ingredients float around in a liquid matrix. By holding the temperature at the point where the glaze is still slightly molten but just beginning to stiffen, the crystals form, with their size being determined by the amount of time they remain in this state. (Typically 3–5 hours). The kiln is then shut off and cooled naturally.

Making a Crystalline Glaze

There are three main ingredients in a crystalline glaze. Zinc oxide and silica make up approximately 25 parts each of the glaze and these are the crystal formers. They come together to form zinc silicate. The remaining 50 parts are the various ingredients that form or flux the glass melt, which can include boron, magnesium, calcium, lithium, sodium, and potassium. 
However, some of these ingredients are soluble in a glaze. Therefore, it is to the potter’s advantage to use a frit. When using a frit, a crystalline glaze could consist of only three ingredients: frit, zinc oxide, and silica. This combination, in the right proportions, will produce a crystalline glaze.

The most commonly used colorants are cobalt, copper, iron, manganese, nickel, and rutile. Less common are gold, silver, uranium, and some rare earth metals. These can be used alone or in combination with each other.

 Let’s look at these ingredients individually. Most crystalline glaze recipes will call for calcined zinc oxide. Almost all of the zinc oxide you buy today is calcined, so there is no need to calcine it yourself. Check with your glaze supplier to ensure your zinc is calcined. If not, calcining is not a difficult procedure; place the zinc in a bisque bowl and heat it to cone 06–04, which means essentially putting it through a bisque firing. This will drive off any absorbed moisture. Zinc oxide absorbs moisture from the air so it must be stored in an airtight container. Calcined zinc oxide weighs less than uncalcined so make sure you are using calcined as recipes are based on the calcined weight. The silica should be 400 mesh (used for most glazes—but double check), because this particle size makes it easier to get a complete melt and no nucleation (the beginning of crystal growth, based around an unmelted zinc-silicate crystal).

There are many frit manufacturers on the market, which becomes confusing as frits are primarily made for industrial applications, and manufacturer names change. The most common frit used by crystalline potters is readily available and is called Fusion-75. It was formerly called Ferro 3110. If you ask your supplier for Ferro 3110 they usually know what you are asking for but sell you Fusion-75 (the same thing). 

I suggest using one frit and getting to know it well before trying another. Although different frits can give slightly different effects on the glaze, the greater variety comes from the minerals used. If using another frit, the glaze must be altered accordingly. You cannot substitute one frit for another without making adjustments based on the chemical composition of the frit.

Very small amounts of alumina or bentonite are often added to a glaze to help keep the materials in suspension (1–2%). These ingredients must be in very small quantities or the glaze will opacify and become a matte glaze. Adding a small amount (1%) of epsom salts to the glaze keeps the glaze flocculated.

Experimentation should be done first with the colorant. These are easier to adjust than other ingredients and can give the most dramatic results. Start with one colorant and add it to the base glaze in gradual increments. Also try mixing two or more colorants together. Final glaze slurries should be passed through an 80-mesh sieve.

The glaze should be thickly applied by pouring, dipping, or spraying, with a thicker application at the top of the pot, thinning towards the bottom. Once the pot is glazed, it is placed in the collection dish and put in the kiln ready for firing (see “Planning for Glaze Overflow” below).

Very small amounts of alumina or bentonite are often added to a glaze to help keep the materials in suspension (1–2%). These ingredients must be in very small quantities or the glaze will opacify and become a matte glaze. Adding a small amount (1%) of epsom salts to the glaze keeps the glaze flocculated.

Experimentation should be done first with the colorant. These are easier to adjust than other ingredients and can give the most dramatic results. Start with one colorant and add it to the base glaze in gradual increments. Also try mixing two or more colorants together. Final glaze slurries should be passed through an 80-mesh sieve.

The glaze should be thickly applied by pouring, dipping, or spraying, with a thicker application at the top of the pot, thinning towards the bottom. Once the pot is glazed, it is placed in the collection dish and put in the kiln ready for firing (see “Planning for Glaze Overflow” below).

Planning for Glaze Overflow

Precautions must be taken to protect kiln shelves from running glaze. The most typical method is to make either a one- or two-piece pedestal with a dish under it so that the top of the pedestal is the same diameter as the foot ring of the pot. The pot is glued to the pedestal and the excess glaze runs down the pedestal and into the collection dish. The glue may be a mixture of 50% kaolin and 50% alumina or it could be just kaolin mixed with a little water and Bondfast glue. The kaolin and alumina help separate the pot from the pedestal after the firing so the glue mixture should be applied thickly. I glue my pots to their pedestals before they are glazed.

Firing Crystalline Glazes

Most crystalline glaze firings take place in an electric kiln. It is possible to fire in a fuel kiln and that will be discussed later. The kiln must be capable of going to cone 10 or 11 without difficulty. A temperature controller is an asset. Kilns may be purchased with factory-installed controllers or a controller can be purchased separately and installed by an electrician. The controller must interface between the power source and the kiln’s main switching panel.

There are two types of temperature probes on the market: the S type and the K type. The S is more accurate, particularly for cone 9 or above, and is preferred by crystalline potters, although it is more expensive than the K.

Most new kilns come with three temperature probes so a potter can see what is happening in three different locations in the kiln. A laptop computer can be plugged into a jack provided by the manufacturer on some controllers. It can be attached directly to the processor and connected to a computer with KISS. (Kiln Interfacing Software System). This allows one to see graphically what is and has happened in three different areas of the kiln at the same time, and to make any necessary adjustments. During the firing, the actual time and temperature profile can be displayed, logged on the printer and saved on a disc, giving a complete picture of the entire firing sequence. Several kilns can be fired at the same time, and using a remote, the potter can monitor, graph and program firings while away from location. Another advantage is that firings can be repeated exactly, and the programs stored in the computer.

It is possible to fire without a temperature programmer by carefully watching the pyrometer and monitoring the kiln visually, but it requires the potter being present from the time the kiln reaches peak temperature throughout the crystal growing phase.

When the kiln has cooled to the point that the pots can be handled, they can be removed from the kiln. Lifting them by their collection dishes avoids the possibility of the pot separating from the dish and the dish falling back into the kiln.

Take a small hammer and tap around the collection dish to separate the pot from the dish. Usually the pot will separate. If not, use a glass cutter and score around the seam where the foot rim of the pot meets the top of the pedestal. Then take a small chisel and gently tap around this seam with a hammer.

Another method for removal is to use a propane torch, either the type used for spot welding or a crème brulé torch. The flame is aimed at the join line as the pot turns on a banding wheel. The pot quickly breaks away from its base. In both methods, it is necessary to wear safety goggles to protect the eyes from flying glass particles.

The bottom of the pot may have sharp edges of glass that can cut the hands. A silicon carbide grinding wheel can be used to remove the pieces of glass and smooth the bottom, and that may be all that is needed. To get a really smooth bottom, a diamond grinding pad is helpful. Whatever grinding method is used, wear a dust mask to protect your lungs from the dust.

 by Diane Creber

Reduction Firing Crystalline Glazes

Safety is always a factor when firing all kilns, but especially when fuel is introduced. These are flammable materials and one must never leave a kiln unattended throughout the reduction period. Good ventilation is a necessity and reduction should not be attempted unless one has a kiln hood to extract fumes, or the firing is conducted outdoors.

Crystalline glazes contain a large proportion of zinc oxide compared to standard glazes, sometimes comprising as much as 30% of the glaze. Zinc oxide is easily reduced to the metal at temperatures above 1742°F and the metal alone melts at 786°F and boils at 1697°F. Even slight reduction is sufficient to extract the oxygen which results in the loss of the zinc. Therefore any reduction at these temperatures or above will take away the oxygen, leaving a boiling metal. The boiling metal volatilizes and is lost. It is widely advised that zinc oxide be used only in fully oxidized or neutral firings. Because of this, it was long believed that crystals could not be grown in a reduction atmosphere.

Before electric kilns were available, crystals were grown in a neutral-to-oxidizing atmosphere in gas kilns. The crystalline glazed pots would be placed in saggars to protect them from any reduction that might occur. However crystalline glaze potters have been recently experimenting using reduction to enhance the pre-formed crystals, or introducing reduction during the final stages of the crystal growing phase, to completely alter the glaze.

The preference has been for electric kilns for firing crystalline glazes. Once potters realized that reduction can alter the glaze and create many more exciting effects, they started looking for ways to introduce reduction. With electricity, the ability to reduce is somewhat limited, although possible. But firing crystals in a gas kiln and using reduction as part of the process is also possible, using specific firing schedules.

At a recent workshop (Hamling studio, Warwick, New York), reducing in standard and custom-made electric kilns was demonstrated at two different temperatures (1500°F down to 1250°F and 2000°F down to 1850°F), and there were several firings with variations of these methods.

When reduction takes place after the crystals are grown and at temperatures below 1900°F, the zinc oxide is unaffected. This is sometimes done at the end of the initial glaze firing.

Crystalline glazes containing minerals that are affected by reduction (rutile, copper and iron) can be fired in oxidation and then refired in reduction. They no longer need their protective dishes and pedestals, which may be removed before firing. Before loading the kiln, a small fired dish is placed under the bottom peep hole inside the kiln. The kiln is fired to 1500°F and then is either shut off and reduction started as the kiln cools naturally down to 1250°F, or reduction can be introduced while the temperature drops to 1250°F using a temperature controller.

Reduction requires a fuel, and there are various ways the fuel can be introduced. One method of introducing fuel is to use an IV bag filled with the fuel (oil or denatured alcohol), available from some drug stores or a hospital supply store. When the kiln has reached the temperature to start reduction (1500°F), the bag is suspended above the kiln and the end of the tube is inserted into a protective ceramic sheath that goes into the kiln above the ceramic dish. The point of entry into the peep hole should be sealed with clay or fiber blanket to make the area airtight and to keep the sheath in place. Just below the bag on the tube is a small dial that regulates the rate of flow from the bag.

The difference between reducing at the higher and lower temperatures are obvious in the finished results. For instance, Gold Stuff Glaze (see recipe below), when fired in oxidation produces cream-colored crystals on a white background. When reduced at the higher temperature, the results are a blue background with gold colored crystals ringed in white. The same glaze reduced at the lower temperatures produces a deep purple background with olive green to gold crystals ringed in gold.

It is the firing that gives the diversity of glaze results, and using only one or two glazes gives the potter a whole palette of amazing color.

Crystalline Firing Program for a Digital Controller

Every kiln is different, and what measures 2350°F on one kiln may be out by several degrees on another. Experimentation is necessary to find out the firing temperatures that work best. Cones should be used to measure total heatwork, and the rate of temperature climb to reach top temperature should be noted. (See Techno File, February CM, p.12). To measure temperature drop and soaking temperature, a pyrometer or temperature controller is used.

The following is a very simple guide for programming a temperature controller for a crystalline firing:

    * 150°F/hr to 250°F. No hold (slow climb initially to dry the glazes)
    * 300°F/hr to 2200°F. No hold
    * 108°F/hr to 2345°F. No hold (The rate of climb is slowed to allow for less wear on the elements. This should get to cone 10 at 2345°F. Some potters hold at peak temperature for a few minutes.
    * 325°F/hr to ~2000°F*. Hold for 4 hours. Often potters set “9999°F to 2000°F” on their temperature controller, which tells the controller to lower the temperature as fast as possible.
    * Kiln off.

*2000°F is a temperature in the middle of the crystal growing range. Crystals can be grown a little hotter or cooler than this temperature (+/- 100°F). If held at the hotter temperature range, the crystals may be more bar shaped or double-axe-head shaped. At the cooler end, they tend to round out and more resemble flowers. Raising and lowering the temperature within the crystal growing phase results in growth rings in the crystals.

Typical Crystalline Glaze (cone 10)

            Lithium Carbonate                     00.1

            Zinc oxide (calcined)                 30


            Fusion Frit 75 (Ferro 3110)       44.9

            Silica                                          25.0

                                                             100 %

Add:    Bentonite                                   1.0 %

Color Variations:         

            Blue: Cobalt Carbonate                                  0.5–2 %

            Green: Copper Carbonate                                  1–5 %

            Pink/Tan: Manganese Dioxide                           1–5 %

            Yellow/Green: Red Iron Oxide                          1–4 %

            Green: Nickel Oxide                                           1–2 %

            Yellow: Rutile                                                     1–4 %

These colorants can be combined, but when doing so use less of each ingredient.

 by Diane Creber

Gold Stuff Glaze (cone 10)

            Fusion Frit F644                     45.1

            Zinc Oxide (calcined)             25.3

            Bentonite                                 0.7

            Molochite                                 0.4

            Silica                                      28.5

                                                        100.0 %

Add:    Rutile                                      5.0 %

            Ilmenite                                  3.0 %

Ceramic Pigments and Stains: How to Get Great Color in Your Work

Ceramic Pigments and Stains: How to Get Great Color in Your Work by Bill Jones.  Ceramics Monthly, October 11, 2010.

Prepared ceramic pigments, commonly referred to as “stains,” expand the potter’s palette with infinite possibilities. Pigments provide a wide range of color possibilities in clay bodies, inglazes, underglazes, and onglazes.

In order to get a full range of consistent ceramic colors, pigments are used with metallic oxides and salts, many of which are soluble or toxic, to make them stable. By combining these elements, along with clays, silica, and alumina, the industry has come up with 44 different calcined pigment systems covering the entire color spectrum.

Pigments solve some of the problems found in using just plain oxides. For example, when pure chrome oxide is used as a colorant to obtain green, it may fume or volatilize in the kiln leading to absorption into the kiln bricks and shelves. The oxide may also effect the color of the glaze. If tin is present in a white or pastel glaze, the chrome reacts with the tin to create a pink coloration. In addition, if any zinc oxide is present in the glaze, you’ll get a dirty-brown color. The solution is to use a green pigment, of which there are several. One such system is the cobalt-zinc-alumina-chromite blue-green pigment system, where varying the amounts of cobalt and chrome oxides produces a range of colors from green to blue-green to blue. Mason 6244 is an example of this pigment.

Using Pigments

Depending on the use, pigments may be used straight and just mixed with water, but they are more commonly added as colorants in clay bodies and glazes. Some pigments are specifically formulated for clay bodies while some are not suitable at all. When used in clay, pigments are usually used in engobes and slips as a coating for clay rather than pigmenting the entire body. The exception to this would be using stains to tint porcelain for neriage work.

Use in concentrations of 10–15% in clay, using more or less depending on the intensity needed. Add the pigment to the slip and sieve through a 120x mesh screen to ensure adequate dispersion.

Pigments can be used in underglazes for brushing onto greenware or bisque. If used only with water as a medium, some glazes may crawl, so for best results, mix the stains with a frit (for example, Ferro frit 3124). Begin with a mix of 85 frit/15 pigment and test. Transparent gloss glazes applied over the top will heighten the intensity of the colors.

When using pigments in glazes, usually in concentrations of 1–10%, a little more care must be taken because some pigment systems react with materials in a glaze. Some pigments are affected by the presence, or lack of, boron, zinc, calcium, and magnesia. Manufacturers provide information on specific reactions. While most pigments can be used in both oxidation and reduction atmospheres, some are limited to certain maximum temperatures. Again, this information is available from manufacturer websites.

To achieve a wider palette, most pigments can be mixed to achieve even more colors. The exception is that black pigments cannot be used to obtain shades of gray because blacks are made from a combination of several metallic oxides. If low percentages are used, the final color is affected by the predominant oxide in the black pigment.

Testing and Safety

When using pigments alone or in combination with other pigments and/or oxides, you’ll need to test them with the frit, glaze, and slip bases you intend to use. A good starting point is either using some of the published recipes or using frits. Because pigments are expensive to manufacture, their cost is higher than that of ceramic oxides, but you’ll find most suppliers will sell ceramic pigments in quantities as small as ¼ pound.

Finally, safety is always an issue. Suppliers are required by law to provide a Material Data Safety Sheet (MSDS), and there are different precautions listed with each pigment or family of pigments. Make sure you read and follow the instructions listed in the MSDS for safe handling.

When used as underglazes, surfaces coming into contact with food must be covered by a food-safe transparent glaze, and glazes containing pigments should be tested for food use.