glazenerd

As a friendly reminder from my front yard--

Yes. I took 4 years of wood working, and 4 years of architectural drafting. Small engine repair, lathe, metallurgy, welding, and 2 years of mechanical drafting. 2 years of electrical wiring, a semester of electrical motor repair. I took Home Ec my senior year, but I already knew how to cook. Some farm classes, which were pretty much useless because I was a farm boy anyway. I excelled in chemistry, always had a curiosity about it. Enrolled in a local college to major in chemistry until I realized I would spend the rest of my life in a cubicle- so I dropped out.
Tom

Rebs:
Pinholes come from off-gassing feldspars: blisters come from off-gassing inorganics- primarily from iron disulfide. (sulfides) You either slow the firing down between 1250-to-1800F, or slow the kiln down from 2050F up to peak (cone5/6). The brown splotches of color in the tan area of your glaze is a goodindicator of iron bearing clay: in this case iron disulfide. When a crater forms around the blister, and barren clay can be seen in the center of the crater: almost always inorganic materials burning off. -- Tom

As a friendly reminder from my front yard--

In Southern California elementary school in the 50s we learned to write the alphabet by printing and then cursive (my youngest grandchild, 21,  cannot read or write in cursive  ). We learned to fold, cut, color, draw, paste (yum!) and glue (Elmers doesn’t taste the same anymore, either).  
My Mom was ‘crafty’ and my Dad was a mechanic/woodworker. They grew up during the Depression, so making well and making do were basic understandings.  I spent my free time making stuff, dolls and doll clothes and paper dolls with my best friend, and reading about making stuff. Sewing and cooking classes in 8th and 9th grade, wished I could take woodworking in High School, but that was for boys. I made a lot of my own clothes, also with a best friend (we wanted and needed to be original). Some Art teachers were inspiring and remembered fondly.
I’m jealous of folks who had ceramics in high school. It wasn’t until my second attempt at Junior College, age 22, that I finally found my clay calling   Hanging out with other clay people led naturally to construction, brick laying, booth building, photography, Volkswagen repairs, computer skills for brochures and flyers and accounts, and a sometimes economically perilous but fulfilling life of creativity.

Yes. I took 4 years of wood working, and 4 years of architectural drafting. Small engine repair, lathe, metallurgy, welding, and 2 years of mechanical drafting. 2 years of electrical wiring, a semester of electrical motor repair. I took Home Ec my senior year, but I already knew how to cook. Some farm classes, which were pretty much useless because I was a farm boy anyway. I excelled in chemistry, always had a curiosity about it. Enrolled in a local college to major in chemistry until I realized I would spend the rest of my life in a cubicle- so I dropped out.
Tom

The term is pyroplasticy: caused by low alumina. (16% alumina would be my guess). Pyroplasticity can be compounded by naturally occurring fluxes. If you want to use it as a clay body; then you need to add 20% kaolin (any kind) to raise the alumina level. Kaolin has 37% alumina typically. It could be used as a slip, but like glaze: low alumina levels makes it unstable. It could be used as a glaze with low levels of flux additions at cone 5. However, low levels of alumina will make it unstable.  Using it as terra cotta at cone 04 (as mentioned above) is the best option.  You have iron disulfide bearing clay; which goes brown once you get above cone 3 or so.
Tom

Yes. I took 4 years of wood working, and 4 years of architectural drafting. Small engine repair, lathe, metallurgy, welding, and 2 years of mechanical drafting. 2 years of electrical wiring, a semester of electrical motor repair. I took Home Ec my senior year, but I already knew how to cook. Some farm classes, which were pretty much useless because I was a farm boy anyway. I excelled in chemistry, always had a curiosity about it. Enrolled in a local college to major in chemistry until I realized I would spend the rest of my life in a cubicle- so I dropped out.
Tom

Ryan:
Particle size is not the only indicator of plasticity: although it plays a predominant role. The scientific community measures in um; but most pottery literature is given in mesh. micron, or sub-micron particle definitions. Older pottery and geology books cite "clay mineral"; which has been replaced with "montmorillites." Bentonite and hectorite both are classed as "clay minerals: which by definition means a mineral with clay properties. In addition: plastic characteristics are also determined by aluminum levels, and naturally occurring calcium, potassium, and sodium levels. Particle structure also plays a role: a 1/1 particle (kaolin) is very low plasticity; while 2:1 particles (ball clay, bentonite, hectorite) can be very high in plasticity. If you want to do a deep dive; I will send you some links.
Tom

I'd dip that in water then put in plastic for a while.

The article by Leela is nicely written, a great place to start if you've never done this before.
A couple pictures from an expedition to Sheep Mountain, about two hours from Anchorage. A massive landslide the day before deposited a thick layer of clay right by the roadside. It was happy timing, we had planned a long hike up the mountain to get to a bed of kaolin that's documented there. It was very plastic, threw like a dream, and didn't even shrink that much. Unfortunately this clay was nowhere close to pure kaolin. At cone 03 it softened and expanded into a puffy marshmallow like consistency. The bowl in the back held a sample at cone 6. Bubbly foam.

Typo back a bit
AmphoTERIC is what you need.
What is Tina's source of water?
Could be  alkaline already?

Final before I go to work (suppose be retired- yeah right!  Once I figure out a measuring system for you; I am also going to do a PH test. I use a PH meter to mix certain glazes, and to check alkalinity levels of certain clay blends. The short term fix will to be add a specified amount of baking soda to your water; stir and dissolve it: then pour off the water- leaving the residue behind. That alkaline water will then become what you mix your clay with. I will PH check it to make sure it is not too high. There only needs to be a minimum amount of PH to break the effects of acidity; do not need much.
Tom

Tina:
I used baking soda for an experiment because you did not have access to feldspars. Clay reacts to two extremes: acidity creates strong flocculation; but equally strong alkalinity (above 9.8 PH) also creates very strong flocculation. The PH of baking soda would be classified as "caustic" in the clay chemistry world. For that reason, I asked you to google search potassium fertilizer; trying to figure out an alternate source that is readily available to you.
Tom

Tina:
One final experiment: take a golf/ ping pong ball size piece of your brown clay. Add just a few drops of water and wedge it it; needs a little more moisture. Then put a "pinch" of baking soda on it; wedge that in. Then add a second pinch of baking soda; then wedge that in. Let it sit about an hour. and do the coil test- wrap it around you finger. That will tell me how much acidity/ and or positive charges (iron and alumina) is effecting plasticity. Once I know that; this weekend I will measure out and weigh a clay I believe similar to yours. Then weigh out how much bentonite. I will post a ratio: x amount of bentonite for every cup of clay. You can then mix by multiplying that base recipe. Unless you have a scale; then life gets easier.
Tom

The term is "amphoretic."  Certain acids (vinegar/lemon juice) when mixed with other acids create a specific reaction that creates alkalinity. One of those "freaks" of chemistry. The Amish use a mix of vinegar and herbs to treat acid indigestion for that reason. The other thing missing in this equation is: commercial clay bodies have 10-35% feldspar content: your body has 0-1%- so the intended reaction will not occur.  I will resist my urge to go on a long rant about monovalent sodium ions.
Tom

and that is how you know it is sodium bentonite: it swelled, became gelatinous. Calcium bentonite does not have that same reaction.
Tom

When you wet process wild clay: 1. Put your clay in a bucket large enough to cover it completely with water. Agitate it, then let it sit for 1-4 hours; until you see a clear water film on top. Pour off the excess water, then slowly pour into another bucket until you reach the layer that has debris. Throw the debris out. Then pour your clay through a pillowcase, and hang it up somewhere until the excess water drips out. Allow it to dry down to a workable clay consistency.
Tom

and that is how you know it is sodium bentonite: it swelled, became gelatinous. Calcium bentonite does not have that same reaction.
Tom

Tina:
When deciding what to add or remove in a clay body; it comes down to application and firing technique. 1. Functional or non-functional. Functional has specific limits, non-functional has none. 2. Firing- pit, kiln, raku: different firing techniques create their own demands on clay. So before I can answer: how do you plan on firing it? What temperature (cone) do you plan on firing it to? Are you making functional or non-functional pieces.
Tom
 

Tina:
When deciding what to add or remove in a clay body; it comes down to application and firing technique. 1. Functional or non-functional. Functional has specific limits, non-functional has none. 2. Firing- pit, kiln, raku: different firing techniques create their own demands on clay. So before I can answer: how do you plan on firing it? What temperature (cone) do you plan on firing it to? Are you making functional or non-functional pieces.
Tom
 

and by the way: like glaze- plenty of failed recipes as well.
Tom

and by the way: like glaze- plenty of failed recipes as well.
Tom

Hi Terra:
Moly crystals as they are more commonly known as fall under the Crystalline Glaze category. Molys are complicated, and there is a step learning curve in learning how to develop the glaze, and firing them. Like crystalline; the glaze is bought up to a peak temperature: then lowered to a specific temp and held for several hours. (Called a ramp hold). I have been firing crystalline for awhile now; and still pull my hair out when firing molys. So be forewarned: you are about to dive down a very deep rabbit hole.
If your kiln does not have a programmable controller, and if your kiln does not hit cone 10: no point in trying. You will spend several months educating yourself, and a few more months of trial and error before you get these dialed in. You will not find information on this site, and as you have already found out- or find information anywhere. Crystalliziers as they refer to themselves, closely guard their favorite recipes and firing schedules. I do know where we happen to hang out: Facebook- Working Crystalliers.
Tom.

It has been close to a decade since I bought any commercial clay. Years ago, I put the same crystalline glaze on five different commercial porcelain bodies, and got five different results. That single incident sparked my curiosity about clay formulation; which turned into an obsession for awhile. I do crystalline tile almost exclusively; and every commercial porcelain body I tried- warped. From that, I developed a crystalline body that actually promotes crystalline growth; instead of hindering it. I developed a porcelain tile body that I roll out on 2 x4 x 1/2" luan, and let it sit until it pops off on its own. My days of flipping, weighting, and spending hours trying to prevent warping are long over. Few years back I developed an extensive line of colored porcelain: which I use from time to time. Local supplier wanted me to distribute it; but not really had the time to get that involved. A shoulder injury from a few years back has also hindered that endeavor.
My bigger interest of late has been collecting and processing locally sourced clay. It holds my interest; breaking it down and figuring out how to make it a workable body. I have samples sent to me from across the US, and on rare occasion- other countries. Rather fascinating to see the results from iron disulfide, hematite, and magnetite samples. Still toying with the idea of bringing back a semi-load of hematite clay from NE Oklahoma- best looking cone 6 results I have ever seen. I have been contacted by potters across the globe for in depth discussions on how to fix their naturally sourced clay issues. The most complicated puzzle was sub-tropical laterite from India; took awhile to find the solution. (43% total iron/alumina content). Collecting and processing natural clay is more popular than most realize; but it is not a topic that is widely discussed here.
A few months back another interest has taken center stage in my life: so clay may have to take a back seat for awhile.
Nerd -- the pic below is Oklahoma hematite.