Raw Mineral Glaze：Crafting the Jian Zhan (Part 2)

Last time, we discussed how three types of clay from Shuiji Town, Jianyang, Nanping, Fujian, form the unique iron body that sets Jian Zhan apart from other tea wares.

But the iron body is only the skeleton. What truly gives Jian Zhan its fascinating soul is its ever-changing, mysterious metallic glaze patterns. Without these metallic patterns, Jian Zhan would be nothing more than an ordinary black-glazed cup.

What creates the “myriad colors” of Jian Zhan’s glaze are, similarly, two seemingly ordinary elements: raw minerals and plant ash from Shuiji Town, Jianyang.

—Raw Minerals

These locally sourced minerals are quartz and feldspar stones with extremely high iron content (around 15%, right first from the up picture).

After being crushed and ground into a slurry, they form the main component of Jian Zhan’s glaze. They serve as both the glaze base and the primary source of its metallic (or glass-like) luster.

—Plant Ash

The plants used for making the ash are also locally sourced from Shuiji Town, including grasses, legumes, rice straw, rice husks, and millet husks（right second from the up picture）.

Plant ash provides potassium carbonate, as well as trace elements such as calcium, magnesium, silicon, phosphorus, iron, manganese, and copper. Its main role is as a flux, helping to lower the melting point of quartz.

Additionally, it introduces infinite possibilities for variations in the glaze.
By mixing raw mineral slurry and plant ash in specific proportions, the raw mineral glaze formula for Jian Zhan is created.

It is the diverse formulations and the unpredictability of the firing process that give rise to the endlessly varied glaze patterns—embodying the timeless charm of Jian Zhan: “One color enters the kiln; myriad colors emerge.”