US Pigment Stains in Porcelain Clay Body

US Pigment Stains in Porcelain Clay Body Each of these tests was mixed with 100g porcelain clay body in amounts of +2%, +4%, +8%. The +8% was also mixed with black stain (Mason 6600, mixed about 25% black and 75% color).

Categorized as Tests

Visualizing Blend Types

Tests using traditional line, triaxial, and biaxial blends can teach us a lot about ceramic chemistry.  But sometimes they feel limiting.  What other possibilities are there?  Arranging a series of line blends into a “complete graph” might be illuminating.  And instead of a flat biaxial, what about a three-dimensional pyramid/tetrahedron?  What if blends went 3d? I’d love to hear the #glazenerd army’s… Continue reading Visualizing Blend Types

Categorized as Tests

SiC Additions to Clay Bodies

A simple blend test adding Silicon Carbide (SiC) to a clay body. Wanted to see if I could induce reduction effects in an oxidized electric kiln environment.

Categorized as Tests

Lipstick Purple Biaxial

“Painted” Biaxial based on Tom Coleman’s beautiful Lipstick Purple. Part of my “Painted” series of tests prepared for @northernclaycenter’s “Six McKnight Artists” exhibition.  Each row has a set Alumina level, while each column represents a specific Silica:Alumina ratio.  Coleman’s original recipe lies on the bottom row (Al2O3 0.4) between the second & third columns (Si:Al… Continue reading Lipstick Purple Biaxial

Qing Porcelain Stone Tests

These are melt tests of different types of porcelain stone from sometime at or before the Qing dynasty. Iron or blue qinghua underglaze was used to write place names and other notes on each test. Porcelain stone is an amazing material that primarily comes from a number of mines near Jingdezhen. Combining porcelain stone with… Continue reading Qing Porcelain Stone Tests

Orton Cone 6 Clear Glazes

Having not fired cone 6 since college, I started by first testing a number of clear cone 6 glazes on I also studied up on cone 6 glaze chemistry via Matthew Katz​’s Advancing Glazes course and his papers: Boron in Glazes,  Mid-Temperature Glaze Science,  Glaze Safety/Durable Glazes Presentation. Click here for full image of… Continue reading Orton Cone 6 Clear Glazes

Tichane’s Tests

Some of Robert Tichane’s glaze tests and reproductions of Chinese Glazes donated to the Freer and Sackler Galleries:

Categorized as Tests

Glaze Transparency Test

Recently I’ve been wondering if there’s a reliable way to test glazes for transparency.  A method that would allow one to compare results from different firings and glaze types. Paint manufacturers have a system for testing paint opacity that uses a black and white card from which a contrast ratio can be calculated. The primary manufacturer is Leneta.… Continue reading Glaze Transparency Test

Mixing test glazes

Carefully measure out each ingredient into the bowl, placing into separate piles so that any extra material can be easily removed.

It’s important to wear a NIOSH certified mask whenever using dry glaze materials. I guess mixing up glazes isn’t that big of a deal, but I’m sharing my technique just in case there are some absolute beginners out there. I find it easier to use a digital scale, see my article here. Glazes “don’t travel well”, in… Continue reading Mixing test glazes

Orton Cone 10 Reduction Glaze Line Blends

Leach 4321 Line Blends

Leach 4321 is a simple, reliable glaze that we can use to compare coloring oxides. All of the following glaze variations can be found on Glazy:

Categorized as Glazes, Tests

Digital Scales for Weighing Glazes

Calibrating the Ohaus SP202 and SP4001 digital scales

After years of using simple balance scales to measure out glazes, I finally decided to invest in a better setup. I couldn’t find any triple-beam scales for sale in Jingdezhen, so instead I purchased a cheap 200-gram digital scale from a local shop.  I was delighted at how much simpler and faster it was to mix up… Continue reading Digital Scales for Weighing Glazes

Triaxial testing

A lot of potters in China still seem to mix glazes the old-school way- one cup of this, two cups of that.  And strangely enough this technique seems to work pretty well for complex traditional materials.  Being a foreigner I tend to make things overly complicated.  I am also terrified of mixing up a great glaze… Continue reading Triaxial testing

How I Make Glaze Test Tiles

Test tiles can be loaded quite close together in the kiln.

October 2020 Update I’ve simplified my test tiles. Now, the test tiles themselves are just simple slabs of clay. But I make test tile holders out of a strong clay. Flat, Square Test Tiles Flat test tiles cut from slabs are ideal. You can easily make them from any type of clay. No need to… Continue reading How I Make Glaze Test Tiles

Categorized as Tests

Porcelain Stone Glazes

Jingdezhen Porcelain Stone There are a number of types of porcelain stone mined throughout Jingdezhen and the surrounding countryside.  Some are more suitable for making porcelain clay, while others are traditionally used for glazes.  It is difficult to know how similar modern-day porcelain stone is to traditional materials.  During the few years I have lived… Continue reading Porcelain Stone Glazes