Pearcy001 wrote:
I have read a couple of times that the arched chop is for the good stuff then the fan chop (the one that looks like a ginko leaf) is only used for the really limited stuff with unique glazes and extra detailed pieces.
In your experience do you think that is the case? Or do you think some people are trying to look into it too hard and it is simple an evolution of the potter's chop?
I agree with this summary as being the case, but I think there is more to add. This is my take on Koyo chop marks:
All the run-of-mill pottery produced by the Koyo workshop has the standard Koyo hanko (chop mark):
Koyochop.jpg
While in general this grade of Koyo is the least expensive, it is not always the case. Nor does it mean that this grade is necessarily of lesser quality – it is usually A-grade quality Tokoname-ware. However, there are some caveats to price in this class of Koyo. Over the years, the clay type that Koyo used has changed, and some of the glazes have also evolved from what they used to be. Vintage Koyo’s standout easily as they were based on a dark coloured clay – well, actually a light coloured clay with a dark coating. This gives the pots a different look, feel and character to the more modern pots, which are based on a light coloured clay. Personally, I prefer and chase the vintage Koyo’s, because of their characteristics, and because some of the glazes are no longer produced today. If one of these vintage run-of-mill pots grabs my attention, I will not hesitate to pay a premium for it. Here is an example from my own collection of a vintage Koyo in oribe glaze based on the dark clay (see my avatar):
Koyovintchop1.jpg
And here is an example of a more modern oribe in the light clay:
koyo mod.jpg
It has to be said that whether this grade of Koyo pot is vintage or not, the variation in glazes that come out of a wood firing can affect desirability (and price) within a single kiln-firing. An example is the unique patterns and hues on any oribe glazing which can vary from plain greens to beautiful mottled blues and greys – the better one perceives the glaze pattern to be, the higher the price fetched for the pot. So this vintage/modern rule can be huge generalisation.
The arched (or half-moon) chop indicates (from my understanding) that the pot is Koyo’s own work, and fired in his own kiln:
Koyo half moon.jpg
I have rarely seen this arch-chop stamped on anything bigger than a shohin-size pot. These pots will sometimes come cloth-wrapped in their own wooden presentation box, which gives the impression of a premium product. However, I have seen shohin Koyo’s with the standard hanko also come in these presentation boxes. It is generally perceived by westerners that the half-moon chop is stamped as a premium product (because some of them come in a box?), but in my observation it does not attract a noticeable premium. In reality, the same clay and glazes are used, and in traditional wood-fired kilns, the quality of a glazed pot will not be known until it is retrieved from the kiln after firing – so IMHO this perception of premium grade may be a bit of misguided belief.
The fan, or ginko chop is nearly always accompanied by the standard chop, with Koyo’s signature in between. Here is an example from my collection:
koyobigginko.jpg
This ginko chop generally indicates a commissioned pot/custom order – so by default is an indication of limited quantity. It can also include an extra inscription (as shown on the right hand side in the picture above) which may detail who the pot was commissioned by, or maybe for what event the pot was commissioned. These pots can have unique glazes or detailed pieces – basically whatever the customer ordered. As such, they tend to command a premium price, as they are a bit more unique and collectible.
Another Koyo chop you may come across is known in the western world as the fuji-chop, as it resembles Mt Fuji:
koyofuyoen.jpg
The Mt Fuji chop is actually an indication that the pot was commissioned by the Fuyo-en Nursery in Omiya, on the outskirts of Tokyo. Anyone who has visited Fuyo-en will know it is considered one of the benchmarks in terms of quality deciduous trees. So the fact that this nursery commissioned Koyo pots makes perfect sense in regards to the glazes available. These pots also generally command a premium price for much the same reason as the ginko chops – uniqueness and collectability. They are also considered very useable, having been commissioned by a nursery for use to pot trees, rather than just to sit on one’s pot-collection-display-cabinet.
I will reiterate that this information is merely what I have learned in my travels, and if anyone has more accurate information to add – please do.