Testing of Yixing Teapots

by Patrick Gorman August 14, 2026

The Yixing Teapot industry has changed significantly over the past century, particularly in the last forty years. Since the late twentieth century, chemical additives—including colouring oxides, waterglass, and barium carbonate—have become common. In the last few years, however, the Chinese and international markets have increasingly favoured a return to pre-modern processing techniques that avoid additives. The growing availability of laboratory testing also makes it possible to provide more detailed data on the clay than was previously possible.

EDXRF Testing of Yixing Teapots

We have sent sample teapots for each batch of clay currently available from Lin Hanpeng and Chen Chunhong’s studio for testing by an independent lab using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). EDXRF is a preferred method for testing, as it is non-destructive, and provides immediate data on the elemental composition of the material. More about EDXRF testing can be read here.

The results for each batch are included at the end of this article, and will also be added to each listing where applicable in our Yixing Teapot page. The results show no chemical additives for these clays. Of particular note is the section for Barium (Ba) in each testing sheet showing that the numbers are within the expected range found in the raw ore.

Barium is found naturally in these deposits, showing up in the hundreds of parts per million. Results in the thousands of parts per million indicate barium carbonate added. For an example of teapots that have failed testing for amounts in this range, see here and screenshot below. Barium carbonate is added by some studios to prevent efflorescence, the appearance of cloudy white areas on the surface of the clay if it is left too long without being worked.

Examples (source: Facebook) of teapots that have failed EDXRF testing for certain additives (in red), including Ba:

A few considerations:

1. The compound Barium Carbonate is quite toxic in its raw form but it reacts with other compounds in clays and also decomposes during firing at high temperatures in a kiln, to form stable, insoluble minerals. The primary concern with barium carbonate has been with the danger of handling it prior to firing. You can read more about all this here and here.

2. Barium is already present naturally in Yixing clay in minute amounts.