THE MOST IMPORTANT DISTINCTION

Overglaze or Underglaze — Everything Else Follows From This

The key variable is not the tradition or the price. It is where the decoration sits relative to the protective glaze. This determines dishwasher safety, microwave safety and how much care a piece needs.

  • Overglaze Decoration

    Pigments applied on top of the fired glaze, then fired again at lower temperature (700–900°C). The decoration sits above the protective surface — it is more susceptible to alkaline detergents, mechanical abrasion and heat cycles.

    What uses it: Most Kutani hand-painting, gold and metallic accents on any tradition. Identifiable by running your fingertip across the surface — you may feel the decoration very slightly raised.

    → Always hand-wash. Never microwave if metallic decoration is present.

  • Stable glazing

    Pigments applied to the unfired clay body, then covered with a transparent glaze and fired at high temperature (1,250–1,300°C). The decoration is physically sealed beneath the protective glaze — it cannot flake, fade or be scratched away.

    What uses it: Koransha's cobalt blue patterns, most Mino-yaki natural glazes (ash, iron, celadon). The surface feels completely smooth across both glaze and decoration.

    → Gentle dishwasher cycle acceptable. Microwave safe if no metallic accents.

1 2

Three Japanese Porcelain Traditions — What They Are and How They Behave

We work with three traditions of Japanese ceramics, each with a different production history, glaze character and care requirement. Slight variations in tone, texture or brushwork are part of the character of handcrafted ceramics and are not defects.

  • Kutani Ware

    A high-fired porcelain body with hand-painted overglaze decoration applied in layered mineral pigments. Kutani is characterised by its bold five-colour palette — red, green, yellow, purple and dark blue — and by kinrande (gold brocade) work. The overglaze technique means the decoration requires more careful handling than underglaze work.

    • High-fired porcelain body — strong and durable
    • Overglaze decoration — requires hand-washing
    • Gold and metallic variants — never microwave
    • Slight brushwork variations are expected and authentic
    learn more 

  • Koransha Porcelain

    mperial-grade white porcelain with cobalt underglaze decoration, produced by Koransha in Arita for over 140 years. The cobalt blue is fired beneath the protective top glaze at over 1,250°C, making it significantly more durable in daily use than it appears. Pieces with gold overglaze accents revert to hand-wash only.

    • Fine white porcelain body — very low porosity
    • Cobalt underglaze — dishwasher safe (gentle cycle)
    • Pieces with gold accents — hand-wash only
    • Glaze variations in translucency are part of the character
    learn more 

  • Mino-Yaki Ware

    High-fired ceramics from Gifu Prefecture in natural ash, iron and celadon glazes. The dense clay body and stable glaze chemistry make Mino-yaki the most operationally straightforward tradition in daily use. Most pieces are dishwasher and microwave safe. Natural glaze variations — color pooling and texture — are intrinsic to the tradition.

    • Dense, high-fired clay body — impact resistant
    • Natural ash, iron and celadon glazes — very stable
    • Generally dishwasher and microwave safe
    • Glaze pooling and surface variation are not defects
    learn more 
1 3

GENERAL CARE

How to Care for Japanese Porcelain

These steps apply across all three traditions. For tradition-specific guidance, see the full care guide in our journal or the individual product listing for each piece.

The most important single rule: dry pieces immediately after washing. Standing moisture at the unglazed foot rim is the most common cause of long-term damage to Japanese ceramics in everyday use.

delicate hand-wash of Japanese ceramic bowl with a hand-painted illustration

Identify the glaze type first

Overglaze (Kutani hand-painting, gold accents) — hand-wash only. Underglaze (Koransha cobalt, Mino-yaki glazes) — gentle dishwasher cycle acceptable.

Wash with mild detergent and a soft cloth

Never use abrasive pads or scouring powder on any Japanese ceramic. A small amount of mild washing-up liquid on a soft cloth or non-abrasive sponge is sufficient.

Allow pieces to cool before rinsing

Thermal shock — pouring cold water on a hot piece — can cause glaze micro-cracking over time. Allow pieces to cool to room temperature before rinsing.

Dry immediately — do not rack-dry wet

Dry each piece with a soft cloth after washing. The unglazed foot rim is porous — prolonged contact with moisture can cause staining and long-term damage.

Store with padding between stacked pieces

Place a soft felt pad between every stacked piece. The foot rim is abrasive and will scratch the glaze below it. Never stack without protection, regardless of how careful you are.

ON VARIATION

Slight Variations Are Part of the Character

Handcrafted Japanese ceramics are not manufactured to machine tolerances. Slight variations in glaze tone, texture and brushwork are produced by the firing process, the mineral composition of the glaze, and the hand of the individual artisan who made the piece.

Care FAQ

Is Kutani porcelain dishwasher safe?

No. Kutani pieces with hand-painted overglaze decoration must be hand-washed. The overglaze pigments sit above the protective glaze and are vulnerable to alkaline dishwasher detergents and heat cycles. Repeated machine washing will cause the colors to fade and lose their depth. Pieces with gold or metallic overglaze must also never go in a microwave.

Is Koransha porcelain dishwasher safe?

Koransha pieces with cobalt underglaze decoration and no metallic accents are generally safe for gentle dishwasher cycles. The underglaze decoration is sealed beneath the protective top glaze at over 1,250°C, making it significantly more resistant than overglaze work. Use a mild detergent and disable the heat-dry function. Pieces with gold or overglaze accents must be hand-washed.

Is Mino-yaki dishwasher safe?

Most Mino-yaki ceramics from Paean™ are dishwasher safe. The natural ash and iron glazes are stable and the clay bodies are dense enough to tolerate regular machine washing. Check individual product listings — specific pieces, particularly those with overglaze decoration, may vary.

Can Japanese porcelain go in the microwave?

Plain glazed and underglaze-decorated Japanese porcelain without metallic accents can generally be used in a microwave. Never microwave pieces with gold, silver or platinum decoration — the metal will arc, damaging the piece and the appliance. Check individual product listings for each piece.

Why does my piece have slight variations in glaze or color?

Slight variations in tone, texture and brushwork are a natural and expected characteristic of handcrafted Japanese ceramics. They are produced by the firing process, the mineral composition of the glaze, and the hand of the individual artisan. These variations are considered part of the character of the piece, not a defect.

How should I store Japanese porcelain without damaging it?

Always store stacked pieces with a soft felt pad or cloth between them. The unglazed foot rim of Japanese porcelain is abrasive and will scratch the glaze surface of pieces below if stacked without protection. Store in a dry location away from direct sunlight. Pieces in regular use suffer far less storage damage than pieces kept in a cabinet.

READY TO USE THEM

Pieces Made for the Table, Not the Cabinet

Every piece in our catalog is selected for daily use — durable enough to earn its place, refined enough to stay in view.

to cataloghow to select