A triaxial blend is a great way to incrementally test 3 ingredients in combination with a base glaze, and in combination with each other. A triaxial blend is like three line blends (one on each side of the triangle) that meet in the middle. A typical “21-point” triaxial looks like this:

If you look closely, you’ll notice that each side of the triangle is just a line blend. Look at the right side of the triaxial above and follow the path from tile #1 down the right side of the triangle until you get to tile #21. You’ll see that it’s a line blend of material A in diminishing increments from the top to the bottom right corner. Conversely, material C incrementally decreases as it moves from the bottom right to the top. 

The numbers following A, B, and C on the above chart are not grams – they are percentages (*although in theory, one could design a test that would follow this chart as grams, but you will follow it as percentages).

So, take a look at tile #1 in the diagram above and you’ll notice that it says “A=100”. This does NOT mean you’ll have 100 grams of material A –- it means you’ll have 100% of your maximum test amount for material A. For example, if you decide to test your material A in 1 gram increments, your maximum A test would be 5 grams of material A. In this example, tile #1 would have 5 grams of A (which is 100% of your test amount), tile #3 would have 4 grams (which is 80% of your test amount), tile #6 would have 3 grams, etc (and the last one, tile #21 would have 0 grams). If you decide to test material A in 2-gram increments, then tile #1 would have 10 grams, tile #3 would have 8 grams, tile #6 would have 6, etc. Some materials are more powerful than others, so the increments you test in will vary for some materials. This is why triaxials are labeling with 100, 80, 60, etc, because your test amount for red iron oxide in one corner of the triaxial might be 5 grams and your test amount for zircopax in another corner might be 10 grams.

Remember that each of your 21 tests will start with 100 grams of your base glaze. The amounts you are adding for materials A, B, and C are in addition to the 100 grams of base glaze that you have already put into each cup.

1. Enter your base glaze (the glaze you are going to test on) into Glazy and batch the glaze to 2100 grams, writing down the amounts for each material.

2. Measure and thoroughly dry mix 2100 grams of your base glaze

3. Weigh out 100g and add it to each cup. You should have nothing left over in the bucket.

4. Weigh out the A, B, and C materials needed for each cup, adding them to the 100g of dry glaze in each cup. To make this part of the process faster, you might consider doing all the A material, then all of the B material, then all of the C material, rather than going cup by cup. 

5. After each cup has all of the materials in it, weigh cup #1 and write that amount down. Then, mix water with it until you get the desired consistency (whole milk). Weigh the cup again to calculate how much water you’ve added. This is a starting point for the amount of water to add to each cup, although the exact amount may vary slightly from cup to cup. It’s important to try and get the consistency the same for each cup.

6. Dip your tiles (make sure they are numbered first) into the cups as you go through the process of adding water to each of them. For example, add water, mix thoroughly, then dip. Then repeat the process on the next tile. If you don’t dip the tiles are go, the glaze will settle before you finish and the dipped tile won’t be an accurate reflection of the glaze.

7. Make sure and record all the infos! Be organized. It’s easy to screw this up. Go slow. Write down everything in your notebook. Re-number your tiles with iron oxide stain if you need to. 

8. At the end of this, you should have glazed 21 test tiles. 

9. Put your test tiles on the cone 10 cart. Or, if your triaxial is a cone 6 test, put them on the cone 6 shelf. 

10. After you put your tiles on the appropriate shelf, CLEAN UP the glaze room. Please, for the love of all things holy, clean up your mess. Please.

So you don’t get confused during this process, it’s helpful to label your triaxial cups like this:

If you are lost on what to test, seek help from your Fearless Leader in Ceramics. Here are some example tests to give you some ideas on where to start:

Temple’s Persimmon base
1. Test with Rutile, Black Iron Oxide, Gerstley Borate (Gillespie Borate)
2. Test with Copper Carbonate, Red Iron Oxide, and Burnt Umber
3. Test with Yellow Ochre, Manganese, and Rutile

Steven Hill “Semi-Clear” (Steven Hill Clear with 7% Zircopax)
1. Test with Rutile, Copper Carbonate, and Red Iron Oxide
2. Test with Burnt Umber, Rutile, Gerstley Borate
3. Test with Cobalt Carbonate, Manganese, Red Iron Oxide
4. Test with Orange (6028), Turquoise (6374), Celadon (6201)
5. Test with Walnut (6108), Mazerine (6300), Celadon (6201)

Missouri Straw base
1. Test with Rutile, Manganese, Yellow Ochre
2. Test with Burnt Umber, Copper Carbonate, Red Iron Oxide
3. Test with Rutile, Black Iron Oxide, Chrome
4. Test with Mazerine (6300), Celadon (6201), and Turquoise (6374)

Cushing Satin base
1. Test with Red Iron Oxide, Yellow Ochre, Burnt Umber
2. Test with Rutile, Red Iron Oxide, Cobalt Carbonate
3. Test with Copper Carbonate, Yellow Ochre, Rutile

Coleman Tea Dust base
1. Test with 3 Mason Stains
2. Test with Red Iron Oxide, Rutile, Copper Carbonate
3. Test with Cobalt Carbonate, Manganese Dioxide, Rutile
4. Test with Copper Carbonate, Red Iron Oxide, Yellow Ochre

Here’s a video of John Britt explaining the 21-point triaxial blend: