Ru-glaze crackle ware
Modern tea ware finished with a deliberately crazed pale glaze and sold under the name of a Northern Song imperial kiln. The crazing is not a flaw and is the reason people buy it: tea enters the cracks and darkens them progressively, so the pattern draws itself over months of use.
Identity
- Category
- Brewing vessel
- Native name
- 汝窯 / 開片
- Romanised
- ru yao, kaipian
- Also called
- crackle glaze tea set, ice-crackle ware, ru ware
- Material
- Porcelain or fine stoneware under a deliberately crazed opaque glaze
- Typical capacity
- 30–200 ml
- Skill level
- Beginner
Porosity
Not porous. It contributes nothing of its own to the liquor, so it can be moved between teas freely and washed with detergent without consequence.
The glaze itself is not porous but it is cracked through, and the cracks reach the body. Liquid enters them and stays, which is why the pattern develops and why the same piece cannot be returned to its original appearance. That is a reason to keep such a piece to one kind of tea, and it is a reason about staining rather than about flavour.
Where it comes from
The name belongs to a Northern Song imperial ware of which very little survives. What is sold today as ru ware is a modern crackle-glaze product referencing it, and the two should not be confused — TeaHQ describes the modern object and does not claim continuity with the historical kiln.
Named here rather than presented as generic equipment. The object belongs to a practice, and TeaHQ describes it from the outside.
If you do not own one
Plain porcelain, which does the same brewing and does not commit you to a permanent stain pattern. If the developing crackle is the appeal, that is a good reason to buy it and it is an aesthetic one.
This one is not marked essential. The tea can be made without it.
Brewing methods it is used for
- Gongfu brewing (gaiwan) — A high-leaf, low-volume, many-infusions approach: a great deal of leaf in a small vessel, steeped for seconds at a time and poured off completely, repeatedly.
Tea types it suits
Care and maintenance
Rinse rather than soak, and never bleach — bleach lifts the colour out of the crackle unevenly and leaves it patchy. Some owners darken a new piece deliberately by brewing dark tea in it; that is a choice, not maintenance.
Other brewing vessels
- Berrad (Maghrebi teapot)
- Boiling teapot
- Brewing saucepan
- Çaydanlık (Turkish double kettle)
- Chawan (matcha bowl)
- Chinese lidded mug
- Cold brew bottle
- Dagwan (Korean teapot)
- Dobin
- Enamel-lined cast iron teapot
- Gaiwan
- Glass teapot
- Glazed stoneware teapot
- Houhin
- Kyusu
- Nixing pottery teapot
- Plastic teaware
- Plunger tea press
- Porcelain teapot
- Quick-brew infuser press
- Shiboridashi
- Silver teapot
- Stainless steel teapot
- Travel gongfu set
- Travel infuser bottle
- Unglazed clay teapot (non-Yixing)
- Western teapot
- Yixing teapot
- Zavarnik (concentrate pot)
Sources
This page is TeaHQ synthesis. No external source stands behind the description, the material or the account of how the object is cared for. Where the record names a tradition, that attribution is TeaHQ’s own reading of common practice rather than a citation.
TeaHQ names no maker, brand or shop and has nothing to sell. Nothing on this page should be read as advice to buy the object — the substitute note above exists because owning it is usually optional.