Pricing pottery and ceramics: firing, glaze, and loss

Ask a potter what a mug costs to make and the answer usually starts with clay. A bag of stoneware, divided by the number of mugs it throws, is a small and comforting number. It is also the least useful figure in the studio, because clay is the cheapest thing that ever touches the piece.

The expensive parts of ceramics are the kiln and the pieces that never come out of it intact. Neither one shows up on a bag of clay, and both are where the money actually goes. This chapter is about costing those two properly, plus the glaze in between, so a mug is priced on what it took rather than on what its raw material weighed.

Everything in the pricing handmade products chapter still applies: materials, plus labor at a real rate, plus a share of overhead, equals your true cost per unit, and your price sits above it at a margin you choose. What follows is what “materials” honestly means when a kiln is involved. If you would rather see that method argued from first principles on a single object before you bring a kiln into it, the guide on pricing handmade products without underpricing yourself does exactly that.

A unit in ceramics is a survivor, not a piece you made

In most crafts, a unit made is a unit you can sell. In ceramics it is not. A form passes through a chain of stages and can die at any of them: cracking as it dries, an S-crack in the bottom of a thrown pot, a blowout at bisque, a glaze that crawls, runs onto the shelf, or pinholes badly enough that the piece becomes a second.

That matters for costing because the survival rates multiply. If a form survives drying at one rate, bisque at another, and the glaze fire at a third, your sellable yield is the three multiplied together, not the best of them and not the average. A chain that looks forgiving stage by stage can be brutal end to end.

So the denominator in your cost arithmetic is not the number of pieces you started. It is the number that reach the shelf as firsts:

Cost per sellable piece = total cost of the batch ÷ pieces that survive to sale.

Written the other way round, it is a loss allowance every good piece has to carry. If your survival rate to sellable is nine in ten, each good piece carries about a ninth again on top of its own cost. If it is three in four, each good piece carries a third again. That uplift is not pessimism. It is the arithmetic of paying for the failures out of the successes, which is the only place the money can come from.

Firing is a material, and it is priced per load

The single biggest structural difference between ceramics and most other crafts is that your dominant cost is charged per load, not per piece. The kiln does not care whether you filled it.

A load’s cost has four parts, and each one is measurable in your own studio:

• Power. Read the kiln’s rated draw off its data plate, then multiply by the hours of your schedule and a duty factor, because elements cycle rather than pulling full power the whole way up. The honest version is to read your utility meter before and after a firing, or clamp a meter on the circuit, and multiply the kilowatt-hours by the rate on your own bill. Do not use a rate you read somewhere; use yours, including any tiered or time-of-use band the firing lands in.
• Elements and thermocouples. These are consumables with a rated life in firings. Replacement cost, including anyone you pay to fit them, divided by the firings you actually get, is a per-load line.
• The kiln itself. Purchase price divided by a realistic lifetime in firings. Amortization is not an accounting nicety here; it is the difference between a kiln that paid for itself and one that quietly did not.
• Furniture and consumables per firing. Shelves, posts, stilts, kiln wash, and the odd shelf you grind, flip, or replace.

Add those and divide by the pieces in the load, and you have the firing cost per piece. Which immediately exposes the most expensive habit in a small studio: a half-empty load costs the same as a full one. Firing at half capacity does not halve the cost, it doubles the firing charge on every piece inside. Packing density is a pricing decision, not a housekeeping one.

Then remember most work is fired at least twice. A bisque load and a glaze load are two separate charges, and a piece lost in the glaze fire has already absorbed both. If you add a luster, decal, or china-paint fire, that is a third. A cost model that charges one firing per piece is understating the machine by half or more.

Glaze is cheap per mug and easy to lose track of

Glaze materials are bought dry, mixed by the bucket, and consumed by coverage, which is why the per-piece cost is so slippery. The number you want is not what a raw material costs per pound, it is how many pieces one mixed bucket glazes, and that varies with your application method more than with the recipe.

Two ways to measure it honestly. Weigh the bucket before and after a glazing session and divide by the pieces you dipped. Or run a bucket to the bottom and count the pieces it covered. Either gives you a real per-piece figure; a recipe printout does not.

Application method changes the answer sharply. Dipping is efficient and gives you most of the material back in the bucket. Spraying loses whatever misses the pot, and that overspray is a real material cost even though it never becomes product. Brushing sits in between and costs more labor. Test tiles consume material too, and if you are developing glazes seriously, they are a line item rather than a rounding error.

Where the per-unit cost lies to you

Five specific ways a ceramics cost per unit comes out too low:

1. Dividing by pieces loaded instead of pieces sold. The most common one, and the one the yield chain above fixes.
2. Charging one firing when the piece took two or three. Bisque plus glaze is the default, not the exception.
3. Treating loss as a bad week rather than a cost line. Losses are not an event, they are a rate. Every good piece has to carry its share of them.
4. Pricing seconds as if they cost less to make. A second cost exactly what a first cost. Selling it at a discount is a decision to accept a thinner margin on that unit, which is fine, but it is a pricing choice and not a cheaper product. Track them separately or your average margin quietly sags.
5. Counting throwing time as the labor. Throwing is the visible part and often the shortest. Trimming, pulling and attaching handles, drying management, sanding feet, waxing, glazing, wadding, loading, unloading, and packing are all real minutes, and together they usually outweigh the time on the wheel. Time one form end to end, once, and use that number.

Measuring your own numbers

None of this needs software to start. It needs a firing log you actually keep, in the same spirit as the batch records and consistency chapter, which is where the rest of this discipline lives.

For each firing, record the date, which kiln, the schedule, the kilowatt-hours if you are metering, the pieces in, the pieces out as firsts, the seconds, and the losses with a cause. Six months of that gives you a per-load power cost, a per-piece firing cost at your real packing density, and a survival rate per form. Those three numbers are the whole ceramics cost model, and they are yours rather than an average of somebody else’s studio.

Clay arrives by the bag and glaze gets mixed by the bucket, so almost every figure above starts life in a unit you do not sell in. Keeping those conversions straight is most of the arithmetic, and the unit conversions article covers how they are handled once the numbers live somewhere other than a notebook. The same firing log is also what turns a year of work into a cost of goods sold at tax time, which COGS for makers explains in plain English.

If you want to see the shape of the stack before you fill in your own figures, the ceramics costing page runs a mug through clay, glaze, and amortized firing so you can watch what the kiln does to a margin.

What carries straight across

Once the kiln and the yield are handled, ceramics is the same business the rest of this playbook describes. Where to sell applies unchanged, and galleries and shops are a wholesale relationship like any other, so the wholesale math in craft fairs and wholesale is the one to read before you pitch a stockist. Ceramics is heavy and breakable, so shipping and packing materials belong in your cost rather than in a shrug at the end of a sale.

One area does need care and is outside what this playbook can settle for you: work intended to hold food or drink brings glaze safety and surface durability into scope, and there are rules about what may leach from a food-contact surface. That is real, it is worth taking seriously, and the labeling and regulations chapter points you at the right authorities rather than guessing on your behalf. Check the requirements that apply where you sell.

Get the load cost, the two firings, and the survival rate honest, and the rest of the arithmetic in this playbook works on pots the same way it works on every other craft it covers.