How stoneware dinnerware is made, and what that means for checks
Stoneware is clay fired hot enough to become dense and hard, then glazed. Plates are usually jiggered or pressed, cups and jugs slip-cast or thrown, and handles stuck on by hand. Pieces are bisque-fired, dipped or sprayed with glaze, wiped clean on the foot and fired again.
Two features of the export trade drive the inspection. First, reactive glazes are popular: glazes that break, pool and change colour where they are thick, so no two pieces look the same. That is the look buyers order, and also where shade disputes come from. Second, many orders are made across several small units and consolidated by one exporter. Each glaze and kiln is a separate food-contact risk, so the lab report must match the unit that made the goods.
The Uttar Pradesh ODOP page names ceramic products for Bulandshahr district (Khurja) and lists tableware, dinner sets, mugs and bowls. Khurja Pottery is a registered geographical indication (IP India application 178, class 21). TradeStat records US$42.90 million of ceramic tableware exports other than porcelain (HS 6912) in FY2025-26 (provisional); that heading also includes earthenware.
What we check on stoneware dinnerware
| Check | How it is checked | What fails |
|---|---|---|
| Food-surface glaze | Inside of every sampled bowl and mug and the face of every plate viewed under a lamp | Pinholes, crawling, bare spots, blisters, rough or underfired glaze where food sits |
| Crazing | Glaze viewed at a low angle; ink or tea wiped on and cleaned off | Network of fine cracks that hold stains and bacteria |
| Glaze and decoration against the tested sample | Colour, decal and rim band compared with the sample sent to the lab; batch codes checked | A colour, decal or rim band that was not in the test report |
| Reactive glaze range | Pieces laid out against light, mid and dark limit samples agreed before production | Pieces outside the agreed range, glaze runs onto the foot |
| Wobble and flatness | Plates and bowls spun or pressed on a glass sheet | Rocking pieces, warped rims |
| Stacking | Six or more pieces stacked; nest of bowls checked | Stacks lean or pieces lock together |
| Foot | Unglazed foot ring checked by hand on a soft cloth | Rough foot that will scratch tables; glaze stuck to the foot |
| Handles and rims | Handle joints checked for cracks; rims run under a finger | Hairline crack at the handle root, chipped rim |
| Thermal screen | Boiling water poured into mugs that were at room temperature, if the protocol asks | Crack or craze after the pour |
| Sets and marking | Set contents counted; back stamp, origin and any "not microwave safe" marking checked | Missing pieces, wrong back stamp, missing use marking |
Common stoneware dinnerware defects and how they are classed
| Defect | Typical cause | Class |
|---|---|---|
| Glaze or decoration on a food surface not covered by a passing leach test | Glaze or decal changed after testing; different unit | Critical |
| Sharp glaze shard or chip on a drinking rim | Handling, kiln debris | Critical |
| Crack at the handle root | Handle attached too dry; drying stress | Major (critical if the handle comes off under load) |
| Crazing on the eating surface | Glaze and body not matched | Major |
| Plate wobbles | Warping in the kiln | Major |
| Pinholes, small bare spots outside the food area | Dust, glaze thickness | Minor |
| Reactive glaze darker than the limit sample | Thicker dip, kiln position | Minor or major as agreed |
Your defect list decides the final class.
Food-contact rules and test claims
- US. FDA judges ceramic ware against action levels for leachable lead and cadmium; cups and mugs have the strictest lead level. See lead and cadmium in ceramics and FDA food contact. In California, Proposition 65 warning levels for tableware come from court settlements, and retailers write them into purchase terms.
- EU. Directive 84/500/EEC sets lead and cadmium limits by article category and requires a written declaration of compliance. Regulation 1935/2004 covers labelling. The Netherlands, Luxembourg and Belgium set much lower national limits in 2026. See EU food contact and LFGB.
- Canada. The Glazed Ceramics and Glassware Regulations (SOR/2016-175) set leach limits by category, including 0.5 mg/L lead for cups and mugs.
- Use claims. Dishwasher, microwave and oven claims are tested, not assumed. Metallic lustre bands and gold decals are not microwave safe and must be marked. Dishwasher resistance of decoration is commonly tested to EN 12875.
Leach tests are lab work; we pull and seal samples from finished stock for an ISO/IEC 17025-accredited lab.
Packing and your purchase order
Plates are packed on edge or flat with paper or foam between each piece; mugs in cell dividers so handles do not touch. Retail gift boxes need fitted inserts. The inspector shakes a packed carton for movement and, where the protocol asks, runs a drop test and opens the carton to count breakage.
- Body (stoneware), shapes and sizes with tolerances, weight per piece.
- Glaze names, colours and the light, mid and dark limit samples for reactive glazes.
- Leach test standard and market (FDA, EU, California, Canada), test frequency, and the unit that makes each item.
- Dishwasher, microwave and oven claims with test evidence; back stamp and marking.
- Set composition, inner packing and carton drop test.
For porous, low-fired clay ware, see terracotta and earthenware.
Sources
- IP India GI registry: Khurja Pottery (application 178)
- ODOP Uttar Pradesh: Bulandshahr ceramic products
- FDA CPG Sec. 545.450, Pottery (Ceramics); Lead Contamination
- Directive 84/500/EEC, consolidated with Directive 2005/31/EC (EUR-Lex)
- Canada: Glazed Ceramics and Glassware Regulations (SOR/2016-175)
- Department of Commerce: TradeStat commodity-wise exports (FY2025-26, provisional)