Ceramics Glazes: what Claude and GPT would buy

Two AI models chose on their own, with no web access. Nobody tested these products: this is what each one says, and how to check it.

Claude and GPT choose the same line: Amaco Potter's Choice

In Arts, Crafts & Sewing, Claude and GPT choose the same brand in 46 of 83 categories.

Claude Opus 5.5 · October 27, 2026

Amaco Potter's Choice (line)

Potter's Choice is a widely used mid-fire brush-on glaze line with reliable layering behaviour on cone 5/6 stoneware.

Not for: Anyone firing low-fire earthenware or ceramic bisque at cone 06, because these glazes will not mature at that temperature.

GPT 6.1 Sol · November 10, 2026

AMACO Potter's Choice PC-20 Blue Rutile

A richly varied cone 5–6 glaze with blue and earthy tones, ideal for adding visual depth to textured pottery.

Not for: Low-fire projects or anyone without access to a suitable kiln.

Mayco Stroke & Coat (line)

Stroke & Coat is an opaque, colour-true low-fire glaze that is easy to brush for detailed painting on bisque.

Not for: Potters firing mid- or high-fire stoneware.

Coyote Clay & Color (brand)

Coyote is known for vivid mid-fire glazes formulated for cone 5/6 electric kilns.

Not for: Low-fire users and anyone who needs ready-to-brush jars rather than dipping quantities.

Spectrum Glazes (brand)

Spectrum offers both low-fire and mid-fire brushing glazes across a large colour range.

Not for: Buyers who want a single tightly matched layering system.

Firing cone match. The glaze cone must match your clay body and kiln firing: low fire is about cone 06, mid fire is cone 5/6, and high fire is cone 10. An underfired glaze stays dry and unstable, while an overfired glaze runs off the pot onto the kiln shelf.
Food-safe labelling. For mugs and dinnerware, use only glazes the maker labels dinnerware-safe when they are fired as directed. Some decorative glazes leach or are not durable on food-contact surfaces.
Application format. Brush-on glazes need two to three coats, while dry or dipping glazes are mixed in buckets. The format determines how much glaze you need and how consistent your results will be.
Runniness. Check whether the glaze is described as fluid, and leave an unglazed margin at the foot. Fluid glazes fuse pots to kiln shelves.
Underglaze vs glaze. Underglazes are for colour decoration and still need a clear glaze over them for a sealed surface. People often mistake underglaze for a finished glossy, waterproof coat.

Shops seen in search results on November 5, 2026. A shop missing here may sell it too. Nothing was checked by a person.

Amaco: Large glaze range, including the Potter's Choice and Celadon lines.
Mayco: Strong in low-fire and paint-your-own glazes, and also makes mid-fire lines.
Coyote Clay & Color: Mid-fire specialist.
Spectrum Glazes: Broad low- and mid-fire range.
Duncan: Long-established low-fire hobby ceramics glazes.

Can I use glaze without a kiln?

No. True glazes must be kiln-fired to melt into glass. Unfired paints are decorative only.