Cab Composition

Essay on Cab Composition, Daniel Bontempo

Why do you like the cabs that you like? Do you cut? How do you decide exactly what shape and where to cut it from the slab? Just a buyer or admirer, what would you say goes into picking a favorite? Lots of elements come together: the shape, the finish, possibly the fame of the material. But what role does color and pattern play? Once the cab is made, it is to like or not. But for the lapidary cutter the decision about the shape has to be followed by a decision about composition. This generally happens while sliding and rotating a template across the face of a slab. Even if a scene or specific elements (e.g., orb, line) are targeted from the get-go, there is generally more than one way to frame or even orient things. How does the cabber decide?  There is a psychological science of aesthetics. Some principals vary if an aesthetic judgment is being made about a face, a picture, a landscape, or a building. Horizons are important in landscapes, proportion is key in architecture; symmetry is paramount in facial attractiveness. Are there design principles that play out in cabochons? Below is a nice 4”x2” slab of Cherry Creek jasper from China. (Come see this great blue & khaki slab with its dark red center line in full color at the next meeting.)

The bold line and fine spider-web pattern offer many design choices. What shape and what composition yield the best possible cab? Admittedly, it loses something in gray-scale xerox, but perhaps still a bit of fun to be had.

Perhaps composing a good photo is the closest thing to composing a good cab. There are few books or web pages that go deeply into cab composition, but many books and web pages can be found on the elements of design in photo composition. Understanding elements of visual design and how they can affect our emotions can also help us make our images more effective. No guideline can ever guarantee success because a successful image depends on lots of things that must come together. It is likely that many artists carry out design intuitively and arrange elements so they "feel right." Common aesthetic principles of photo composition include: line, shape, balance, rhythm, and proportion. A line is an effective element of design because it can lead the viewer's eye. Lines imply motion and can suggest direction or even feelings: horizontal lines imply tranquility and rest, vertical lines imply power and strength; oblique lines imply movement, action and change; curved lines or S shaped lines imply quiet, calm and sensual feelings; lines that converge imply depth, scale, and distance. Basic geometric shapes within images often appeal to the eye. Balance is complex; it can be a balance of color, foreground and background, or even positive and negative space. Together balance and color can create dominant and subordinate elements. Large objects dominate smaller ones and warm colored objects dominate cooler pale colored objects. A centrally located object will draw more attention than one at the periphery. However the center is not the best place to position the most dominant element - usually just to one side of the center is more effective. Rhythm refers to the regular repeating occurrence of elements in the scene. Rhythm is soothing and our eyes beg to follow rhythmic patterns.

Consider the images below. Each is an alternative bolo that might be cut from the Cherry Creek slab. Which would you cut? Do you think any design principles are driving your choice? Remember the darker areas are cool steel blue and the lighter areas are kaki-orange. The center line is dark red. Thin web lines are mostly black.


Do you get a sensual vibe from the wavy lines? Do the cabs at either end of the top row have more balance? This jasper is known for its dense spider-web network of lines, so does bottom left get points for best representing the material? The denser lines, especially on the cooler blue background do give a sense of depth behind the spider web. But I also think the lines look a bit too much like cracks. Maybe that’s why I am not a big Cherry Creek jasper fan. I'm leaning toward the top left. The s-shaped line gives a sensual feeling. The placement in the center gives each side equal balance, and the fact that each side has blue and khaki (criss-crossed) adds to the balance – at least that’s how I see it. How about you?

If you’ve read this far, regrettably there are no clear answers. Hopefully you found the journey thought provoking. Remember, most folks do not consciously keep these concepts in the front of their mind; rather the “best” cab usually pops out as the template is moved about. But, it’s an interesting idea that there may be general principles leading to some agreement about what is best, that it may not be totally random and idiosyncratic.