Clay is sold by grade, and the grading reflects how clean and fine the material is rather than how good it is. Both grades are useful. They are useful for different things, and the cost of getting it wrong runs in both directions.
This guide covers the two grades we produce at Bestari Jaya and which applications each belongs on.
The short version
- Ceramics, mosaic tiles, stonewares, cosmetics — Grade A. The finer, cleaner grade.
- Bricks, roof tiles, general pottery — Grade B. Impurities are tolerable and the price reflects it.
- Not sure? The deciding question is whether the fired surface has to be uniform. If yes, Grade A.
Grade A clay
Grade A is the finer grade, with a chemical composition suited to the finer grades of ceramic material — mosaic tiles, stonewares, and similar work where the fired surface has to come out even. It is also used in construction, and finds its way into cosmetics.
What you are paying for is consistency and the absence of contaminants. In fine ceramic work, an inclusion that would be invisible in a brick becomes a defect in the glaze: a blemish, a pinhole, or a piece that cracks in the kiln. The finer the intended product, the less tolerance there is.
Grade B clay
Grade B is an impure clay, widely used in construction — principally for making bricks, tiles and pottery. "Impure" is a description, not a criticism. For a fired brick, the inclusions that would ruin a glazed tile are simply part of the body, and paying for a cleaner grade buys you nothing the finished product will show.
For brickworks and roof-tile manufacture running continuous production, the practical concerns are supply consistency and moisture content on delivery rather than purity. Both are worth raising at the enquiry stage if you are running to a schedule.
Choosing by application
Clay for brick making
Grade B. Brick bodies tolerate the impurities, and the volumes involved make the price difference material. Where a facing brick has to hold a uniform colour across a batch, consistency of supply matters more than grade — colour variation usually comes from the material shifting between deliveries, not from the grade being wrong.
Clay for ceramic and mosaic tiles
Grade A. This is the application the grade exists for. The fired surface has to be even across the whole tile, and inclusions show.
Clay for roof tiles
Usually Grade B. Roof tiles are a fired construction product rather than a fine ceramic, and the body carries impurities without trouble.
Clay for pottery
Depends entirely on the work. Studio and utility pottery generally takes Grade B. Finer stonewares and anything glazed to a consistent finish wants Grade A. If you are unsure, tell us what you are firing and at what temperature.
An underserved material
Clay gets less attention than sand in the Malaysian market, which means buyers often have a harder time finding a straight answer about grades than they should. If your question is not covered here, ask it — the answer comes straight from the concession, not from a catalogue.
Full product detail is on the Clay page. Other materials from the concession: sand, hardcore stone and tin.
Other guides
Tell us what you are firing
Grade, volume and delivery point — or just describe the product and we will tell you which grade suits it.