What it is
Fired clay sealed with a glaze — a thin layer of glass melted onto the surface. Earthenware, stoneware and porcelain are the same idea at rising firing temperatures; porcelain is vitrified glassy all the way through. Note the imposter: “ceramic non-stick” cookware is not this material — more below.
Why it’s safer
A properly formulated, properly fired glaze is chemically bonded glass: inert, hard, no polymer phase at all, happy at any drinking temperature. Modern dinnerware from reputable makers must pass leach tests — the US FDA’s action levels for lead run down to 0.5 µg/mL for mugs and cups (FDA CPG 545.450) agency. My hot drinks live in glazed ceramic and glass precisely because there’s nothing at 95 °C for the drink to negotiate with.
The honest caveats
Lead and cadmium glazes are real — in specific places. The FDA’s own risk list: traditional low-fired pottery (notably some Latin American and Asian ware), antiques, damaged or heavily worn pieces, flea-market unknowns, and bright orange-red-yellow decoration. A badly fired glaze leaches lead into food — acidic food especially — and no amount of washing fixes it (FDA Q&A) agency. Plymouth’s testing found lead or cadmium in the decoration of most decorated drinking glasses (2017) lab — the same logic applies to painted ceramic rims. Buying handmade? Ask the potter whether the glaze is leach-tested. Home lead-swab kits only catch gross contamination.
Wear matters. Crazing (that fine crack network), chips, and years of dishwasher-microwave cycling open up the glaze. Vintage + crazed + acidic + microwaved is the worst stack — my grandmother’s crazed lemon-curd bowl is décor now.
“Ceramic non-stick” is borrowing the name. Those pans are sol-gel coatings — a silica gel cured onto aluminium with silicone oils for slip. Independent testing found honestly labelled ones genuinely PTFE/PFAS-free (while catching two “PFOA-free” brands that still contained PTFE — “PFOA-free does not mean PFAS-free”) (Ecology Center lab reports) lab. But sol-gel wears fast — the slip depletes within a year or two of hard use — and the category drew fresh scrutiny in 2025 over undisclosed ingredients (EHN) early. I own a set; I treat it as consumable, keep it at medium heat, and I’m honest that it’s the least-settled material in my kitchen.
What I do
Plain modern porcelain and stoneware for plates and mugs, the “I Am Not a Paper Cup” ceramic travel cup for takeaway coffee, no vintage or crazed pieces for food, nothing brightly painted on the food side. The ceramic-coated cookware gets babied — and when it dies, its replacement will likely be cast iron and steel.