food safe ceramics: glazes, lead, and the dishwasher
b.03 · 7 minute read · updated July 2026 · by the studio
Food safe is the most used and least explained phrase in ceramics. It is not a certification stamped on a kiln; it is the sum of sensible choices: a stable glaze recipe, fired to maturity, on a vitrified body, with surfaces that clean properly. Here is what each part means, what the genuine risks are, and the questions that get you real answers from any maker.
what food safe actually means
- The glaze is stable: fired to its intended cone, fully melted, and formulated so acids (coffee, citrus, vinegar, wine) cannot leach metals out of it.
- Colourants are safely bound. The concern names are lead and cadmium; barium and excessive copper get scrutiny in contact surfaces too.
- The clay body is vitrified or fully glazed, so the piece does not absorb liquid and harbour bacteria.
- The surface is functional: smooth where lips and food touch, cleanable, not flaking.
the lead question, honestly
Lead made historic glazes glossy and bright, and it leaches into acidic food. Modern australian studio pottery is effectively lead-free: commercial glazes sold by australian suppliers are formulated without lead, and no serious contemporary maker uses it on functional ware. The genuine caution zone is elsewhere: antique and vintage ware, souvenir pottery from travel, and bright low-fired imports. Those belong on shelves, not lunch tables. If in doubt, home lead-test swabs from the hardware store cost a few dollars and answer the question in minutes.
crazing: charming, and a hygiene question
Crazing is the fine crackle network that appears when glaze shrinks more than its clay, explained properly in glazing basics. On a vase it is pure character; our crackle-glazed moon jar is deliberately crazed. On food surfaces it deserves more thought: on a porous earthenware body, crazing lets liquid into the clay, which stains, harbours bacteria, and can sour. On fully vitrified stoneware the risk drops sharply because there is nowhere for liquid to go. The practical rule: crazed earthenware is for display; crazed vitrified stoneware is fine for dry and occasional use; daily coffee belongs in uncrazed, high-fired ware.
shivering and chips: when to retire a piece
Shivering (glaze flaking off in slivers, the opposite fit problem to crazing) retires a food piece immediately; it sheds glass. A chip is gentler: the exposed clay on vitrified stoneware is inert and safe, just unglamorous. Chips on porous earthenware will drink and stain. And a clean break can be worth repairing beautifully; ask about kintsugi before you bin anything loved, though gold-seamed repairs retire a piece to dry service.
dishwasher, microwave, oven
| appliance | vitrified stoneware | earthenware |
|---|---|---|
| dishwasher | yes, gentle cycle preferred; decade-proof in practice | hand wash; thermal cycling and soaking age it fast |
| microwave | yes, unless metallic lustre decoration is present | usually, but porous pieces can heat alarmingly as absorbed water boils |
| oven | cold-oven starts only; never onto a hot rack | no |
Every piece in our catalogue is high-fired stoneware with stable studio glazes, and each listing states its dishwasher and microwave position plainly. The longer keeping-it-beautiful routine lives in caring for handmade ceramics.
common questions
how do i know if a glaze is food safe?
Ask the maker what glaze it is and what cone it was fired to; commercial glazes from australian suppliers are lead-free and rated food safe when fired to maturity. For vintage or imported ware, use a cheap lead swab test.
is crazed pottery safe to use?
On vitrified stoneware, crazing is mostly cosmetic and fine for occasional use. On porous earthenware, crazing lets liquid into the clay and the piece is better kept for display or dry goods.
can handmade pottery go in the dishwasher?
High-fired stoneware and porcelain from a competent maker, yes, on a gentle cycle. Earthenware, lustre decoration, and repaired pieces should be hand washed.
does old pottery contain lead?
It can. Pre-1990s glazed ware, souvenir pottery, and bright low-fired imports are the risk categories. Modern australian studio pottery is effectively lead-free. Test antiques before eating off them.