After re-reading my post the other day, I came to the conclusion that it really wasn’t that helpful.  Not to me, at least.

No, to properly write up an overview of the creative process, it should really be set in order.  So in bullet points, here is the thought process that led to the layout for the final shot:

• Examine the object.
  What did I want to show?  On reflection, I wanted to show the almost-reticulated pattern on the back, the edges and how it flattens out on the bottom, and the ridged crevice that is effectively the entrance to the shell.
• Find a background.
  I needed a solid surface that would compliment the shell, while still being different enough to really show contrast. My options: a concrete floor (too hard, would have to get down), a soft wooden floor (too much surrounding light), a mottled-glass table (dusty, dirty, distracting, slightly greenish), a metal-grate table (didn’t compliment, distracted), and a wooden table (arguably, distracting).  I settled for the table.  It was more comfortable, had easy-to-control lighting (environmentally speaking), and nice, warm tones.  Being brown, it worked well with the the shell itself.
• Position the shell.
  The first thing to do is place the shell.  What am I showing? In the case of the ridged middle, I needed that to be visible.  From the left, right, top, bottom, other? To my mind, it didn’t matter – but since the ridges were primary, I put them to the left.  Western eyes start by looking at the top-left, so I tried to help them out here.
• Position the primary/key light.
  The primary light for this object should bring the most contrast to the most important part of the item.  Again, the ridges – so I angled it to be from camera left, pointing at the ridges.  After a test shot, I moved it slightly further forward, too.  This gave a slight emphasis to the ridges. It made them stand out more.
• Position the secondary/fill light.
  The primary gave a lot of light on one side.  As a result, the far side fell off into complete shadow. As such, I lost the shine to the right, along with the reticulated pattern and the dappled spots in the middle of the image (the edge of the cowry). I want them to be well lit, but not quite as well lit as the ridges.  Enter flash #2.  There is no softbox on this, so it’s a strong, bare bulb.  Way too powerful.  Enter the diffuser: the Oceanic catalog, which was nearly solid white.  By positioning it properly, I could reflect the flash off of it & create a larger, softer light source.
• Take test shot #1.
  The first one was at a stab-in-the-dark shutter speed of 1/140 at f/8.  Key was set at 1/32nd power, fill at 1/64th  At this point I find that only part of the image was in focus. A large part of the background was underexposed, too – the table was almost black, not the warm tones of orange and brown that should have been there.
• Take test shot #2.
  For greater depth of field, I bump it up to f/11.  Shutter speed goes down to 1/60th.  I now find: still slightly lost on focus, but better.  The background is OK, but the overall feeling is underexposed, like there isn’t enough light.  It’s flat.
• Take test shot #3.
  Shutter at 1/40th, aperture at f/14.  I’ve really cut down the aperture now, so I bump up the power to 1/8th on the key and 1/16th on the fill.  The results are still… uninspiring.  Not quite enough light – but nothing blown out.
• Take test shot #4.
  Shutter and aperture stay in place.  Flash up to 1/4 power on the key, 1/8th on fill.  Slightly overpowered – the  areas with sheen are slightly blown out, but everything else looks pretty much where it ought to be.
• Take shots, wrap.
  Considering the slightly blown-out highlights to be acceptable, I go for it.  In post (with RAW) I should be able to recover most of them.

I’ll note: each time I move the shell to a slightly different position, it required moving the flashes slightly & re-taking test shots.  Generally speaking, this didn’t require changes to the shutter speed or aperture.

Another view of this specimen:

Cowry, alternate angle

(Note: slightly different from the previously shown shot, this one had a goal of showing the lip at the front of the shell, along with the reticulation on the back.)