How enamelware is made
Enamelware is steel coated with glass. Mugs, plates, bowls, pie dishes, colanders, jugs, buckets and pots are pressed from low-carbon steel sheet. Handles are spot-welded on. The steel is cleaned and pickled, then dipped or sprayed with a ground coat that bonds to the metal and fired in a furnace until the glass fuses. One or more cover coats give the colour, followed by speckle, splatter or decals and another firing. Rims are rolled and either enamelled, often in a contrasting dark colour, or capped with a stainless band.
The finished surface is hard and easy to clean, but it is glass. It chips if dropped, and wherever it chips, the steel underneath rusts. Two firing faults are typical. Fish-scaling is crescent-shaped flakes that pop off when hydrogen trapped in the steel escapes; it can appear days after firing, so very fresh stock carries a hidden risk. Pinholes and bubbles come from gas or dirt on the steel.
Enamelled cast iron is made the same way on a cast body; read it with our cast iron cookware page. Enamelled iron and steel household articles (HS 7323 94) were worth US$50.04 million of exports in FY2025-26 (TradeStat, provisional). We have found no official source naming an enamelware cluster, so we name no town.
What we check on enamelware
| Check | How it is checked | What fails |
|---|---|---|
| Chips | Rim, base ring, handle welds, spouts and lid edges checked under light, inside and out | Chip exposing dark ground coat or bare steel |
| Fish-scaling and flaking | Surfaces checked at an angle for crescent flakes; firing date of the lot asked | Flakes, crescent marks, enamel lifting near welds |
| Pinholes, bubbles, specks | Food surfaces checked with a magnifier at arm's length and close up | Pinholes through to the ground coat, burst bubbles, black specks |
| Crazing | Surface checked at an angle under raking light | Fine crack network in the enamel |
| Colour, speckle and decals | Pieces lined up against the approved sample and colour standard | Shade outside the range, heavy or missing speckle, decal crooked, torn or bubbled |
| Rim | Finger run round the rim; stainless bands checked for gaps | Exposed steel edge, rust, sharp rim, loose band |
| Handle welds | Handles pulled and twisted; weld spots checked for enamel cracks | Movement, cracked enamel round the weld, rust at the weld |
| Base flatness | Pots and pans set on a glass plate | Rocking base on pieces sold for hob use |
| Labels | Care and use labels read against your artwork | Missing hob, oven or dishwasher instructions where claimed |
Common enamelware defects and how they are classed
| Defect | Typical cause | Class |
|---|---|---|
| Loose enamel flakes on a food surface | Fish-scaling, poor ground coat bond | Critical: glass fragments can enter food |
| Lead or cadmium above the agreed limit in the lab report | Lead-bearing frit or cadmium pigment in bright colours and decals | Critical |
| Chip exposing steel | Knocks in handling, thin enamel at the rim | Major |
| Rust at the rim or handle weld | Exposed steel, enamel cracked at the weld | Major |
| Pinholes on a food surface | Dirty steel, gas in the coat | Major |
| Decal misaligned or bubbled | Poor application before firing | Minor or major by visibility |
| Speckle or shade variation | Hand-applied splatter, firing variation | Minor if within the sample range |
Your defect list decides the final class.
Lead, cadmium and food contact rules
- Test method. EN ISO 4531:2022 sets a test method for the release of metal ions from enamelled articles in contact with food, with limits, covering items used to prepare, cook, serve and store food. Labs use an acid leach approach like the one used for glazed ceramics; see lead and cadmium in ceramics for how those tests work.
- EU. Regulation (EC) 1935/2004 Article 3 applies. There is no EU-specific measure for enamel, so buyers name EN ISO 4531 or national rules in their specification. See EU 1935/2004 and LFGB.
- US. FDA treats food contact ware that leaches lead as adulterated, and no regulation authorizes lead in cookware. See FDA food contact.
- California. Lead and cadmium are on the Prop 65 list. Many retailers set their own leach limits in purchase terms. See Prop 65.
- Decorative pieces. Enamel signs, planters or display mugs not meant for food should be labelled so; otherwise buyers and authorities assume food use.
Leach tests are arranged through lab testing coordination. The inspector pulls and seals units of each colour and decal, because the risk sits in specific colours rather than the whole order.
Packing, transit and your purchase order
Most enamel chips happen in packing and transit, not in the furnace. Mugs and plates stacked bare knock rims together; a paper sleeve or separator between each piece prevents most of it. Mugs packed in individual boxes should not move inside them, and handles should not press on the next piece. Cartons must be packed tight so stacks cannot shift. The inspector checks separators, inner box fit and a drop test where agreed, and looks for chips in the packed cartons, not just on the line.
Put these in your purchase order:
- Steel thickness, number of enamel coats and rim type.
- Colour standard, speckle reference and decal artwork, with a sample range.
- Chip definition: size and position allowed on rims, bases and handle welds.
- Lead and cadmium test standard and limits for each colour and decal.
- Hob, oven and dishwasher claims, and the tests behind them.
- Packing: separators, inner boxes and maximum stack height.
For glazed ceramic mugs and plates, see stoneware dinnerware.