Luni teapots, personal collection of author. 

Editorial Conversation: Chapter 8, Section 8: Luni Ore and Clay

Jason M Cohen
Jason M Cohen

The episode is also available on YouTube and Spotify.
A full transcript is included on the episode page and below:

[00:00:00] Jason Cohen: Hello everyone, I'm Jason Cohen, the author of an Introduction to the Art and Science of Chinese Tea Ceremony. Today we're discussing Book Two, Chapter Eight, Section Eight, Luni (绿泥) Ore and Clay. Here to talk about this chapter is our editorial team, Patrick Penny,

[00:00:19] Pat Penny: Hey, hey!

[00:00:20] Jason Cohen: Zongjun Li and Emily Huang.

[00:00:22] Emily Huang: Hey.

[00:00:23] Jason Cohen: My first question, luni (绿泥) seems to be one of the least understood or perhaps least of the zisha ores. What has been your experience, both past and recent, with luni (绿泥) clay wares?

[00:00:35] Emily Huang: I've had little to almost no experience with actual luni (绿泥) wares. So I've only seen pictures of it, I've read it in books, but not the exact real thing. And I think it's because the ore itself is so rare. It is very different to the common, reddish color that we are familiar with teapots. So oftentimes it can lead to a higher possibility of fake ones.

So for me, it's still a legendary kind of ware thing that I've never really seen in real life.

[00:01:10] Jason Cohen: I want to push back on that a little bit because, consider even in the Tea Institute where we had access to antiques and rarity wasn't an issue, we had some very rare wares. We had no luni (绿泥), the Institute didn't have a luni (绿泥) teapot.

So it's something about more than rarity, right? Was it some type of cultural disinterest? We've talked about the gradients of rarity in the past. In theory, luni (绿泥) is even more rare than zhuni (朱泥), but how rare is any of this, right? These teapots are available. We could go, we could purchase a luni (绿泥) teapot now.

Why didn't we do it when we had the resources in the Institute?

[00:01:46] Emily Huang: That's a good question. I personally think that because of the color and the rarity, there could be a lot of counterfeits in the market. So it's harder for us to distinguish whether it's real or not.

[00:01:59] Jason Cohen: Pat, do you have a different take?

[00:02:00] Pat Penny: Yeah, it wasn't the hotness, man. I personally didn't use luni (绿泥) my entire time at Penn State because we had no luni (绿泥) teapots and I did not personally purchase a luni (绿泥) pot until this year. I own the same one that's pictured in the chapter that Jason and I and actually Zongjun all bought when we were in Yixing and I think it's just not popular because, there's, I don't want to say that there's not any historically interesting pieces, there are. There's some beautiful historical luni (绿泥), famous pieces, both slightly more historical and contemporary but I don't think there's been this romanticization of luni (绿泥) that we see with many of the other clays. And, zhuni (朱泥) right now, I feel like we talked in the last kind of discussion, has been the hotness the last couple years. I still don't feel like luni (绿泥) has had its time, and I don't think it's coming particularly soon.

I think it'll get there and we have seen some western vendors start to do a couple commissions of luni (绿泥) and talk more about it. I think one of the things that holds it back is luni (绿泥)'s performance with puer and with oolong seems to be hit and miss. Some pots depending on the firing and everything are pretty great and some are so so.

And I feel like everyone on the western end is just looking for pots for puer and oolong and so luni (绿泥) is just not what they're reaching for. It's not, the supreme branded crocks or anything right now. So maybe give it five or six years and we'll see if that changes.

[00:03:31] Zongjun Li: That's an interesting point. I feel like luni (绿泥) has been probably one of the more, I don't know, mystified teapot out there compared to all the other clay types in the market. Because of the name luni (绿泥), people especially regular consumers, they would always assume that the color is going to look green one way or another. Actually I have a pretty recent experience with luni (绿泥) by walking into a tea shop in Chaozhou and asking for some teapot samples for me to see. Of course looking for a Chaozhou teapot.

But this guy has a array of neon green color teapots sitting on the shelf and he's calling them luni (绿泥) but that's not what luni (绿泥) looks like. They got the name from some shaded color from the original ore, not the firing color, not the end product's color.

But, I guess a lot of the consumers and also teapot manufacturer just take the name as a symbol of what the teapot needs to look like.

[00:04:33] Jason Cohen: That's a good point. It is more common to see fraudulent artificially colored luni (绿泥). On a similar note, when I was living in Florence, we had a rule that any gelato shop selling pistachio gelato was a bad gelato shop. And it would inevitably be nuclear glowing neon green, and it was obviously artificially colored and artificially flavored. It's very difficult create real pistachio flavor. And maybe the same type of warning needs to be on luni (绿泥) teapots that the fired clay should not be neon green.

It should not glow in the dark. But that's an interesting one. Zongjun, you spend quite a bit of time with other advanced practitioners in mainland China. How frequently does someone pull out a luni (绿泥) teapot? How frequently does someone say, here's my prize teapot for you, and it's an antique luni (绿泥) piece?

[00:05:22] Zongjun Li: Actually I've never experienced that in a tea session with any tea practitioners that I sit down with and drink serious tea. So that's very interesting. And people tend to, to a certain degree, blur the line between luni (绿泥) and duanni (段泥) because the color do look similar to certain degrees.

[00:05:43] Jason Cohen: Luni (绿泥) is categorized into broad variations, including cloudy head luni (绵头绿泥), black ink luni (墨绿泥), and lipini (梨皮泥), in addition to the most common generic luni (绿泥). What's the major differentiation in these materials and would you be able to differentiate them or are they too similar?

[00:05:59] Pat Penny: Talking about the last part there, if I did not see the ore, if I just saw the fired clay, I'm not really sure that I would be able to differentiate any of them.

[00:06:09] Jason Cohen: The black inked luni (绿泥) looks black and the zhima luni (芝麻绿泥) has little speckles that look like black sesame seeds, so you can visually tell them apart, right? Or, is there, are there perhaps generic and cloudy head look too similar?

[00:06:23] Pat Penny: The black ink black after firing?

[00:06:26] Jason Cohen: No.

[00:06:26] Pat Penny: So, that's what I'm saying is I feel like if I looked at the ore for any of these, yeah, I might have an idea but if I look at the fired clay, I have a feeling that they're all going to look like luni (绿泥) to me and I'm not going to be able to tell you which one is which.

[00:06:40] Zongjun Li: Yeah, definitely going to have a hard time. For luni (绿泥), the end color really changed by a lot depending on the region and the firing temperature. You have some baoshan luni (宝山绿泥) looking like a hongni (红泥)or a zhuni (朱泥) even, and you have some zhima luni (芝麻绿泥) being fired into a kind of a duanni (段泥) color, yellowish with some hues of a green color, but overall yellowish color.

So I would say I would be having a very hard time differentiating them from other clay types.

[00:07:13] Jason Cohen: So we know that the color will vary across multiple wares but particularly in luni (绿泥), depending on the mine site and the ore type and the firing temperature. And yet, the scholarships, the literati made a point of differentiating these subtypes, whether the black ink, the lipini (梨皮泥), or the cloudy head.

So what's driving that? It's not just color, right? There has to be some kind of other property that they've deemed as important in order to make this distinction, this variations.

[00:07:43] Pat Penny: So I think something that we see with a lot of the named varieties is slight blends with other clay. So I think the cloudy head luni (绵头绿泥), like forming between layers of zini (紫泥), there probably is some slight inclusion or blend of zini (紫泥) in some of that.

I think you've gone to say that like the lipini (梨皮泥) is often found in adjacencies with tian qing ni (天青泥), and so there's probably some slight, maybe not purposeful blending but you're probably getting some perigenesis, and so there's probably inclusion of other clays which might make those specific named luni (绿泥) clays unique from each other.

[00:08:18] Zongjun Li: Usually these inclusions or blendings might result in a slight green color hue in the ore or on the surface of the ore before it gets fired. So I think that's also perspective, how this type of clay gets named in the first place.

[00:08:34] Jason Cohen: My understanding is it's predominantly textural properties that create these differentiations.

Speaking of blending, when used as a blending clay, what attributes does luni (绿泥) accentuate? Is there a traditional blending for luni (绿泥) ore?

[00:08:50] Zongjun Li: Maybe not an intentional blending in many circumstances, but a natural blending by the mother nature. So you see a lot of these luni (绿泥) especially lipini (梨皮泥), adjacent to, for example tian qing ni (天青泥), or some other type of zini (紫泥), and all these tiny little speckles on the surface of a tian qing ni (天青泥) ore or zini (紫泥) ore.

And a lot of these ceramic artists love that. They love how the end product being slightly speckled with some pear skins texture. And also just a good indicator of the original ore being a more natural, less processed ore.

[00:09:28] Pat Penny: Luni (绿泥) generally has a pretty large grain size, so when blending with something that might be, like a zini (紫泥) that has quite a lot of sha or sand, small particle material, it could help to add quite a lot of strength and potentially help with any kind of breakage during firing. I think the sintering temperature for luni (绿泥) is also quite different than a lot of the other Yixing clays, right?

[00:09:52] Jason Cohen: It is. It's a higher sintering temperature, starting around one thousand two hundred to two hundred thirty, with variations above a thousand two hundred fifty degrees Celsius.

[00:10:02] Pat Penny: So I guess in the blend overall, it would generally raise the average kind of sintering temperature needed for the clay, which could result in a higher fire than maybe what the other blended clays in that would normally be. You could end up with a less porous, denser ware that was more fired than it would normally be.

[00:10:19] Jason Cohen: The teapot that you mentioned, the one that me, you, and Zongjun all bought the same one, do you know if it's blended clay, or cloudy head, or black ink, or lipini (梨皮泥)?

[00:10:29] Pat Penny: We can ask the potter, but I have no idea.

[00:10:33] Jason Cohen: So it really is, we have evidence that it is hard to identify.

Zongjun, you don't know?

[00:10:38] Zongjun Li: No, we gotta call him.

[00:10:41] Jason Cohen: I don't know either.

[00:10:43] Pat Penny: We'll just have to tell everyone that it's the rarest form of luni (绿泥).

[00:10:48] Jason Cohen: It is not in my notes. So, pure luni (绿泥) wares were relatively uncommon before the F1 era. What changed and could this be seen as a positive innovation?

[00:10:57] Zongjun Li: I guess one of the major reason is just the high breakage rate and flaw rate that luni (绿泥) tend to display during firing. And back in the F1 era, part of the main goal is to essentially make money. You gotta sell the teapot in a cost effective way. With such a high breakage rate and this clay has proven itself to be hard to work with, and I guess a lot of the master decided it's just not a good clay to continue working on for a lot of the production line. And also all of the clays are mainly found in Huang Long Shan (黄龙山) region.

So I guess gradually as the production in Huang Long Shan (黄龙山) decreases, we see fewer and fewer luni (绿泥).

[00:11:38] Jason Cohen: Shaft mine number four and the larger shaft mines during the F1 era increase production, right? So was luni (绿泥) supplies falling or were they increasing because they became more common during the F1 era?

[00:11:50] Pat Penny: I would guess increasing, but then at the same time, I think we see, blending of luni (绿泥) as a technology becoming more and more common. And so as we mentioned previously, we know that the pot we own is pure luni (绿泥). But, we don't know what kind of luni (绿泥). Luni (绿泥) as a blending clay, or, when you look at a luni (绿泥) teapot, it's hard to even tell if it's been blended with something.

So that blending technology whether for better or for worse something that really came out of F1 and at least for making money that blending was certainly a successful idea to implement for more structurally sound teapots.

[00:12:24] Jason Cohen: But I'd also say the firing technology, moving from the dragon kilns and the downdraft kilns into the pushback kilns, is really what allowed even pure luni (绿泥) wares to be consistently fired.

That remained relatively uncommon in comparison to the increase in production of other zisha clays yet, before that, we saw very few, exceedingly few, pure luni (绿泥) wares.

My last question. Emily, let's start with you. Were there any surprises for you in this chapter?

[00:12:54] Emily Huang: Not really. For me, it was gaining more depth into this unknown category. Because it is a very uncommon type to see in the common marketplace and less talked of in the tea world. So for me, it was a lot of learning new knowledge.

[00:13:17] Pat Penny: For me, I had heard of lipini (梨皮泥) and zhima luni (芝麻绿泥) but I had not heard of the other types rarer kinds of subforms of luni (绿泥) and I really didn't know much about luni (绿泥) at all. As I said, we, I didn't own a luni (绿泥) teapot until this year, so a lot of the information in this was new to me. I don't know if there was anything that was, like, shocking. I think some of the firing flaws were interesting, and that was new information for me that these show up frequently for luni (绿泥). I think maybe what was the most shocking thing for me was that the picture of the teapot that both I and Zongjun and you own ended up in this chapter, which means you must not own a rare antique luni (绿泥), Jason.

[00:13:57] Jason Cohen: I do not own an antique luni (绿泥). Of the wares that I'm I've been able to collect and find,

I've not managed a pure antique luni (绿泥) teapot.

[00:14:06] Pat Penny: Yeah, biggest upset of the book.

[00:14:08] Jason Cohen: That's is some insightful collection tracking you got going on there.

[00:14:13] Zongjun Li: The most shocking thing to me I guess was back when we were starting to do the research for this clay and just find out that not all luni (绿泥) teapots are neon green. Confusing seeing, the gradient of color that the luni (绿泥) can result into. It's such a journey to to go down this rabbit hole, but it has been a fun one.

[00:14:34] Jason Cohen: Speaking of which, I can't remember if you purchased the same teapot, Zongjun but I have a what's called a jade duanni (段泥) which is white with a green hue.

And I have this luni (绿泥), which is this straw, pale, tan color that looks like a duanni (段泥). And then the white with the green hue looks like a luni (绿泥), but it's actually duanni (段泥). And this is, of course, luni (绿泥).

[00:14:59] Zongjun Li: That's, extra confusing because probably on the market, people will sell the the jade hue duanni (段泥) as a luni (绿泥) for maybe a higher price.

[00:15:07] Jason Cohen: Everyone, that's all the time that we have for today. Thank you for joining us in this edition of Tea Technique Editorial Conversations. Please join us again for our next conversation, duanni ore and clay.


Jason M Cohen

Master of Ceremonies at Tea Technique. Founder & CEO of Simulacra Synthetic Data Studio. Previously: Founder of Analytical Flavor Systems & Founder of the Tea Institute at Penn State (defunct).