There is an old story around here about Nakazato Muan (12th Generation Nakazato Tarouemon, Living National Treasure) finding a really great white clay seam in the Azambaru area of Taku. 　Here it is in Japanese for those of you who can read it:

中里窯は昭和二十一年に石炭使用の角窯を薪用に改造して二十五年まで焼いた。
土は主に多久高麗古窯址近くの多久市北多久の荕(あざん)原(ばる)白土を胎土とした。
この土を見つけた時のエピソードが残っている。
掘り出した土を叺(かます)に詰めて荷車で重利が梶をとり、多久駅まで運ぶ途中下り坂に差し掛かった。
後押ししていた無庵は、下り坂でも押しまくった。はずみのついた車に重利はあわてて梶棒から飛びのいた。
車はそのまま道脇の田圃に突っ込み、荷車は壊れてしまった。
重利が驚いて怒鳴ると無庵は,
「この土で何を作ろうかと考えていたので下り坂に気付かなかった」と重利に謝った。
「親父が俺に謝ったのはあの時がはじめてだった」と重利はいう。

For those of you whose Japanese is a bit rusty, it goes like this:

In the year Showa 21 (1946), the Nakazato kiln was converted from a coal burning kiln to a wood burning kiln, and it was fired until Showa 25 (1950). During this time, Muan mostly used a white clay from the Azanbaru area of Taku.  There is a story, told by his son Shigetoshi, from the day they discovered this clay seam (Nakazato Shigetoshi passed away in 2015, at the age of 85, so he was probably around 16 years old at the time of this story).
So they have all this clay loaded onto a cart, which Shigetoshi is pulling and his father Muan is pushing, to Taku train station.
On the way, they reach a downward slope, and without noticing, Muan keeps pushing  down the slope, and they almost run into a car speeding down the road. Shigetoshi ends up diving to avoid the car, the car ends up in a rice field, and their cart ends up broken.  When Shigetoshi gets angry and starts yelling, Muan says “I was so busy thinking about what I was going to make with this clay, I didn’t notice the slope.”,  apologizing to Shigetoshi.
“That was the first time my father ever apologized to me.”, Shigetoshi commented.

So why, you say, are you telling me all of this? Well, the fabled white clay seam has been looked for now by other potters for decades with no luck, but due to a fortuitous event a few months ago (and several years of looking), I believe I have found it again. Here are some pictures from our excursion out to dig some sample material for testing.

Oh, and lastly, here’s a picture of one of Nakazato Muan’s coil and paddle built jars. This one is made from white clay from the clay seam pictured above. My firing tests have almost the same color as the unglazed bottom section of this jar (although it is hard to see from this dark picture).