Beauty is only skin deep

 But O how beautiful that good quality skin is!!

What is ‘good skin quality’? You might ask

  We often hear the term ‘skin quality’ when the judges give their Sunday walk around talks at your local ZNA chapter show.  And people often talk about a koi’s ‘skin quality’ as if it this thing that only the emperor with no clothes can see!

  Well, as it turns out, there is a major difference between a wild fish’s skin type and a high quality domestic koi’s skin type. If both are healthy they both can be lovely to take in—health and luster make any fish’s skin look bright and glowing with color. And in both cases we can admire and be amazed by the look of the different fishes.

  But high quality skin is a man made thing! It has properties that have been both accidently and purposely brought along over generations of breeding to be what it is today.

   Let’s explore and put into words what good quality skin is in terms of appearance and then let’s go deeper into the actual components that make for that look.

   First, like a lot of amazing art pieces, we are wowed by great quality koi as living art. Not only  is the fish colorful, it is moving color and it is color that can absorb light to make it even brighter and at the same time it can reflect light back to our eyes- leaving an impression that viewers often describe as ‘ unreal’ or ‘surreal’.  The very bright white of high quality skin seems to lose its hard surface borders and tends to give a glowing soft affect. Some describe it as fine glowing porcelain. Others call it ‘cream’ in a translucent porcelain cup (I like that one). In either case, you can see that high quality skin captures the imagination of the viewer. But the white skin itself only acts as the canvas for the true ‘fireworks’ of high quality skin.  The color pattern within the skin lights up the fish!  In very good quality skin, the colors of red and/or black, take on a density that makes koi true living art. In addition to a thick lacquer look, the color also takes on a three dimensional look within the translucent white skin as the fish moves. And the interplay of color at the margins of the color plate interplays with overlapping scales to complete the artistic effect.

   In short, high quality koi skin is dimensional, bright, bold and living! Real but surreal. Nature’s rare genetic material forged by man thru selective breeding.

  So how is this all possible? How can a fish become a work of art? And how can a man change a fish’s skin?

  Well to understand that, we need a brief physiology review—a koi’s skin is made up of layers of different types of cells and fibers. The very top layer is a loose liquid like surface. The next layer down is a differentiation of the top layer and is made of surface color cells and epidermal cells. This layer like all layers is not a flat surface. Instead its tendency is to wrap each scale top and bottom much the way our skin layers wrap our finger nails. This creates the potential for the human eye to see into and thru the top layers and the bottom layers (if the skin is translucent enough).

 The next layer down is ‘the money layer’!  This is the dermis and it is the home of the scale base, some blood circulation, some fat cells, the color cells and the all important collagen fibers that ‘hold the skin together’.  In wild carp, it is a strong layer that protects blood supply and the muscle below. In our koi, it is the canvas that displays the pattern and in that function, is as important in its detail as the pattern itself.

  Let’s look deeper into the dermis layer.  The collagen fibers of the dermis layer are primarily to create strength. Think of them as fibers of a good pair of blue jeans.  They run in semi-different directions so as to make a mesh like structure within the dermis.  But in high grade koi, these fibers tend to run more parallel than in a wild fish and the fibers themselves tend to be much more translucent, both these things allowing light to enter the dermis rather than bound back off the dermis as it does in light reflecting wild skin. Good skin does also contain very high quinine content. And this light reflecting substance is contained in special cells, embedded within the fixed scale  as well as being ‘loose’ within the epidermis and dermis itself.  This creates two effects-  

1)      An interplay with the collagen fibers of light absorbing and light reflecting

2)      A glow to skin

3)      And also a diamond dust affect that we in the hobby call Fukurin

Please note we have covered just the ‘canvas’ or good quality skin and already I think the reader can agree that high class skin in its highest form/grade is a thing of wonder!

But now we get to the feature of high class skin and that is the pattern------

High class skin if often, but not always, blessed with high class color cells. But let’s spend a minute on the pattern itself. 

   In high grade koi, the pattern, that is genetically programmed to grow and mature within the ‘canvas’, is very stable. Its edges and details are, for the lack of a better description, thick and very well defined. The plate does not split or fray. It is as structured as much as the body edges of the koi itself. It is, and this is important, a separate genetic event than the cells within it. That is a bit difficult to imagine initially. But it is important if one is to understand the nature of pattern and color.

  Now for the icing on the cake! Color!! Great quality skin has intense color! This is accomplished in one of five basic ways—

*the size of the cells that hold color

* The number of the cells.

* The depth arrangement of those cells

* The mix of color tones of different color cells

* The mix and interplay of luster and color cells

  This is very important in that, depending on depth, luster and density, the pattern will look either three dimensional or flat when viewed within the right or the wrong canvas. In other words, the genetic traits of the canvas, plate and cell color cell structure must match. Think of the odds!

  Finally, something that most people don’t think about that much—the scales. The scales must be right. Some scales are large, some small, some too dense and some very delicate. Some add to the look of refined skin and some distract. The Japanese refer to ornamental traits on the scales edging. Some can really add to the look and some can be a bit too much. This might be down to a matter of taste but generally speaking scales must work with everything else we have discussed.

  So now you have an over view of what makes for good quality skin in nishikigoi. To take this lesson further, this author suggests that you look at a lot of koi. Your best opportunity is at a ZNA recognized koi dealers shop or a ZNA sponsored koi show.  And to own a few exceptional high class koi is of course another way to become intimately familiar with the details in this article. Remember, there are no perfect koi and it is just as important to recognize short comings as perfection.

  Koi is a hobby for a lifetime.  And as such, represents a life of lessons. Enjoy the journey!   


                                                                                                               James Reilly, ZNA assistant judge