Studio potter · Rhinecliff Hollow, NY

Firing №47 — cone 6, 14 in, 12 out.

A pottery site usually shows finished objects: glazed, cool, on a shelf, at one size. This one shows the arithmetic a gallery photo hides — the fired size, computed from the clay body's own shrinkage rate, and the loss rate, computed from every kiln load, not asserted in a paragraph. The two places on this page that discuss the same fact are mechanically the same fact.

“A mug thrown at 9.5 centimetres was never a 9.5 centimetre mug. It was always going to be the number the clay body's shrinkage rate says it is.” — Iris Calder

The kiln log

Every firing, in order — not Home, About, Services

Across the 4 firings below, this kiln has loaded 45 pieces and fired 40 of them out whole — 5 lost, a rate of 11.1%, about 1 in 9, inside the 5–15% range even experienced studio potters cite for cracking, warping, S-cracks, glaze crawl and kiln accidents. That loss is already inside the price of every piece that survived — see the FAQ below.

№44 2026-06-08 10.0% lost this firing

Stoneware · 10 loaded, 9 fired out whole.

Cone

6

Ramp

standard

Atmosphere

Oxidation

Hold at peak

10 min

Firing №44 — 10 in, 9 out

Result	Count
Fired successfully	9
Lost — S-crack	1

• S-crack: A trimmed mug base, dried too fast under the studio fan — the crack opened at bisque, not glaze.

9 survivors, thrown → fired

№45 2026-07-01 11.1% lost this firing

Porcelain · 9 loaded, 8 fired out whole.

Cone

6

Ramp

slow

Atmosphere

Oxidation

Hold at peak

10 min

Firing №45 — 9 in, 8 out

Result	Count
Fired successfully	8
Lost — Dunting	1

• Dunting: A tall bud vase cracked on cooling through the 573°C quartz inversion — the slow ramp up wasn’t matched by an equally careful cool-down that load.

8 survivors, thrown → fired

№46 2026-07-22 8.3% lost this firing

Stoneware + Porcelain · 12 loaded, 11 fired out whole.

Cone

6

Ramp

standard

Atmosphere

Oxidation

Hold at peak

10 min

Firing №46 — 12 in, 11 out

Result	Count
Fired successfully	11
Lost — Glaze crawl	1

• Glaze crawl: Amber Celadon pulled away from a dusty rim on a plate that wasn’t wiped clean before dipping.

11 survivors, thrown → fired

№47 2026-08-19 14.3% lost this firing

Stoneware · 14 loaded, 12 fired out whole.

Cone

6

Ramp

standard

Atmosphere

Oxidation

Hold at peak

10 min

Firing №47 — 14 in, 12 out

Result	Count
Fired successfully	12
Lost — Dunting	1
Lost — Glaze crawl (shiver)	1

• Dunting: A thick-footed mug, cooled on the studio’s standard schedule, cracked at the same 573°C inversion point.
• Glaze crawl (shiver): Cobalt Speckle shivered off a rim where the glaze layer ran thick — a fit problem between glaze and body, not a firing-temperature problem.

12 survivors, thrown → fired

Firing & Glaze Record →

How a piece gets to you

Collection

Every finished piece across two lines: Stoneware tableware and Porcelain vessels. The largest by footprint is Vase No. 3 at 27.0 cm thrown tall; the widest is Plate No. 6 at 29.0 cm thrown across. One-of-a-kind pieces that have already sold stay listed as Sold rather than vanishing — the firing log above already proves each one existed.

How a piece gets to you

1. Local pickup Preferred whenever it works — no packing risk, and you get to see the whole shelf, not just the one piece.
2. Insured shipping For everything else. Stoneware and porcelain ship double-boxed with a rigid interior liner; insured for the full listed price.
3. Payment Each in-stock piece links to its own Stripe Payment Link below — one object, one price, no cart. Sold pieces stay listed, marked Sold, because a one-of-a-kind object doesn’t stop existing when it sells.

What the label doesn't say

Cone & food-safety table

A vitrified body absorbs under 0.5% water and is dishwasher- and microwave-safe; an under-fired one is porous, regardless of what a listing says. Every body/glaze pair this studio actually sells is fired to cone 6 and vitrifies there — the last row below is a hypothetical, included only to show what changes if the same glaze were under-fired.

By appointment

Studio visit

Open-studio hours run Saturdays, 11am–4pm, and any other time by appointment — email or LinkedIn to arrange one. A visit is the kiln shed, the wheel, and whatever is on the ware shelves drying for the next firing; there is usually a mug or two straight out of the kiln still worth checking for warmth.

Custom work

Commissions

A commission's price depends on size, form complexity and glaze, so it isn't quoted here — it's quoted after the conversation below. The lead time is not a scheduling inconvenience; it's the physics of the process, realistically 3–5 weeks end to end.

1. Throw The piece is thrown to order, sized against the same shrinkage math the catalogue uses.
2. Dry 3–7 days, slow and covered, so the walls don’t dry faster than the base and open an S-crack.
3. Bisque fire A first, lower firing hardens the clay enough to handle and glaze.
4. Glaze Glaze is applied to the bisqued piece by hand, dipped or brushed depending on the form.
5. Glaze-fire Cone 6, oxidation, the same kiln and schedule as every firing in the log above.
6. Cool A full, unhurried cool through the 573°C quartz inversion — the point most dunting cracks happen if it’s rushed.

Name * Email *

What are you asking for? * Choose one A stoneware tableware piece (mug, bowl, plate) A porcelain vessel (vase, tumbler, bud vase) Not sure yet Reference piece, if you have one in mind Message * Intended use (everyday, gift, dishwasher) matters more than a Pinterest board. Send

The studio

About Iris Calder

Iris Calder throws every piece on this page in a converted barn in the Hudson Valley, working a single 10 cu ft electric kiln to cone 6 in oxidation — one kiln, one atmosphere, no reduction claims and no gas kiln. Trained through a two-year studio-assistant apprenticeship before working under her own name; everything on this page is thrown on the wheel, nothing is slip-cast.

Wholesale and press: LinkedIn is fastest, email works too.