Making Ruyao with Agate

(Originally published June 23, 2019)

This week is a follow-up to last week’s post (and a much belated follow-up to our tour of Shan Kiln and Interview with Lee Shanming). After last week’s post, we received a few questions about the use of agate in Song Dynasty Ruyao. 

​Agate, a form of quarts, is believed to be one of the key ingredients in Song Dynasty Ruyao, and was available in the area surrounding the kilns in Ruzhou. Today most true ruyao / fanggu ruyao use silica powder in lieu of agate since it has the same chemical formula - Si02 or silicon dioxide.  While the basic chemical formula is the same, the form of Si02 matters in terms of cost of sourcing and manufacturing. SiO2, whether from agate or silica, is the ingredient that gives ruyao its cloudy depth.
 
When touring Lee’s studio for the first time a few years ago we were lucky enough to see an example of a fanggu piece that was made with agate, but unfortunately we didn’t take any photos of it at the time. We were able to take a few photos after the original post but forgot to write a follow-up.
 
Below is the fanggu ruyao cup made with agate. The cup is one of only a handful produced. This cup was sold to a collector in China a few years back for the equivalent of around $1000 USD.

Below is the same model of cup that was kept and used by the studio. The cup was used for shu puerh. Over a few years the crazing has spread and the cup has become stained from the tea. The lighting is a little different in these photos. The actual colour is closer to the first example above.